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GKE Turns 10 Hackathon, with Amie Wei
Amie Wei is a Sr. Solutions Engineer at HashiCorp and was the winner of last year's GKE Turns 10 Hackathon. It was Amie's first time entering a hackathon and she ended up bringing the prize home with a Cart-To-Kitchen AI Assistant.
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News of the week Links from the interview
Microcks becomes a CNCF incubating project
The CNCF Technical Oversight Committee (TOC) has voted to accept Microcks as a CNCF incubating project.
About Microcks
Modern software teams build applications as collections of interconnected APIs and microservices, and with that architecture comes a significant challenge: how do you develop and test services in isolation when so many depend on each other? Microcks solves this by providing an open source, cloud native platform for API mocking and testing.
With Microcks, teams can instantly turn their existing API contract documents, whether they’re OpenAPI specs, AsyncAPI specs, gRPC/Protobuf definitions, GraphQL schemas, Postman collections, or SOAP/WSDL projects, into live mock servers. Those same assets then power automated contract conformance tests against real implementations. The result is a unified, multi-protocol approach that spans both synchronous REST/RPC APIs and event-driven, asynchronous architectures — a combination that sets Microcks apart from narrower tooling.
Microcks’s key milestones and ecosystem development
Created in February 2015 by Laurent Broudoux, Microcks is a community-driven project with global contributors and adopters, including financial institutions (BNP Paribas, Société Générale, and Lombard Odier) and technology/consulting firms (Deloitte, Amway, and J.B. Hunt).
Since joining the CNCF Sandbox on June 22, 2023, Microcks has seen significant growth in adoption, contribution, development, and ecosystem reach.
Adoption has surged, with container image downloads exceeding 2.5 million in 2025 (triple the 2024 total). Over 34 organizations publicly adopt Microcks, with 13 added in 2025 alone. The project has high community interest, evidenced by 1,800 GitHub stars and 311 forks on the main repository, plus consistent documentation traffic growth.
The contributor base is expanding, totaling 645 across GitHub. The last quarter saw 51 active contributors with an “Excellent” 57% quarter-over-quarter retention rate. In 2025, 167 active contributors represented 35 organizations. Maintainers now include code owners from Yosemite Crew and AXA France, signaling growing community ownership.
Development health is strong: the project was active 342 of the last 365 days. The 12-month average is 288 new pull requests monthly, with an average issue resolution time of 11 days and PR merge lead time of 6 days. The core platform has had 19 releases, with the current stable version being 1.14.0.
Post-sandbox, Microcks has deepened integrations with CNCF projects like Dapr, OpenTelemetry, Keycloak, and AsyncAPI (The Linux Foundation). It integrates natively with Kubernetes and Helm for deployment and connects to CI/CD via Jenkins, GitHub Actions, and Tekton. Testcontainers modules for Java, Node.js, Go, Python, and .NET allow developers to embed Microcks in local test loops.
A word from the Maintainers
“When we first started Microcks ten years ago, the idea was simple: developers should be able to simulate any API dependency, regardless of protocol, without writing a single line of custom code. What we didn’t anticipate was how central that problem would become as the industry shifted to microservices, event-driven architectures, and now AI-powered APIs. Reaching CNCF incubation is a validation not just of the technology, but of the community that has shaped it; 645 contributors, 34 public adopters, and organizations are contributing back because they genuinely depend on the project. We’re grateful to CNCF for the neutral, collaborative home it provides, and we’re energized by what’s ahead: deeper AsyncAPI toolchain integration, AI and MCP simulation support, and continuing to make multi-protocol API testing effortless for every team that builds on Kubernetes.”
— Laurent Broudoux, Creator and Maintainer, Microcks
“The ‘better together’ principle has defined how we’ve built Microcks from the start, with a vendor-neutral design, integrated tools that developers already use, and shaped it by the organizations actually running it in production. In 2025 alone, more than 13 organizations joined our public adopters list, and we saw over 2.5 million container image downloads. That growth isn’t just a number: it reflects teams in financial services, cloud platforms, and enterprise software trusting Microcks at the center of their API DevOps workflows. CNCF incubation gives us the governance foundation and community reach to keep building in the open. The next chapter, including intelligent mocking for AI agents, MCP protocol support, and making contract testing a first-class citizen in every CI/CD pipeline, is one we’re excited to write alongside the community.”
— Yacine Kheddache, Maintainer and Community Lead, Microcks
Support from the TOC
The CNCF Technical Oversight Committee (TOC) provides technical leadership to the cloud native community. It defines and maintains the foundation’s technical vision, approves new projects, and stewards them across maturity levels. The TOC also aligns projects within the overall ecosystem, sets cross-cutting standards and best practices, and works with end users to ensure long-term sustainability. As part of its charter, the TOC evaluates and supports projects as they meet the requirements for incubation and continue progressing toward graduation.
“Microcks addresses a gap that any team building distributed systems on Kubernetes will recognize immediately: the difficulty of developing and testing services in isolation when everything depends on everything else. Across adopters, Microcks has consistently proven itself as the only open source solution capable of addressing API mocking at scale across multiple specifications, such as REST, GraphQL, AsyncAPI, and gRPC, natively on Kubernetes and without vendor lock-in. Microcks demonstrates the kind of engaged, sustainable community that CNCF incubation is designed to support. I look forward to seeing the project continue to grow within the ecosystem.”
— Katie Gamanji, CNCF TOC Sponsor
Main components
Microcks is composed of several modular components:
- Core Server: The main Microcks application, built with Java/Spring Boot, providing the API mocking engine, web UI, and REST API. It ingests API contract documents and serves dynamic mock responses.
- Async Minion: A lightweight companion service handling event-driven and asynchronous protocols (Apache Kafka, MQTT, AMQP, WebSocket, Google Pub/Sub, and more), extending mocking beyond HTTP.
- Operator: A Kubernetes Operator for lifecycle management and automated deployment of Microcks instances in Kubernetes environments, as well as full GitOps support for deploying mocks and executing tests.
- Helm Chart: A production-grade Helm chart for flexible, configurable Kubernetes deployments.
- Testcontainers Libraries: Community-maintained modules for Java, Node.js, Go, Python, and .NET that let developers embed Microcks directly in automated tests.
- CLI: A command-line tool for triggering API conformance tests from CI/CD pipelines, with integrations for Jenkins, GitHub Actions, Tekton, and others.
Project roadmap
The Microcks team is focused on several key development areas to enhance the platform. A major theme is integrating with AI and the Model Context Protocol (MCP), positioning Microcks as a crucial testing and simulation layer for AI-powered APIs and agents.
Microcks is also expanding its support for the AsyncAPI ecosystem, notably by incorporating Kafka contract testing into the acceptance testing infrastructure for the AsyncAPI Generator. Furthermore, the maintainers are committed to growing the Testcontainers ecosystem across more languages and frameworks.
Building on the 2025 OpenTelemetry integration, Microcks will feature continued observability enhancements. Finally, future work includes adding support for more event-driven protocols and advancing the JavaScript dispatcher to enable more dynamic and complex mocking scenarios.
The full project roadmap is maintained at https://github.com/orgs/microcks/projects/1.
As a CNCF-hosted project, Microcks is part of a neutral foundation aligned with its technical interests, as well as the larger Linux Foundation, which provides governance, marketing support, and community outreach. Microcks joins incubating technologies that standardize cloud native infrastructure, enhance observability, and streamline service-to-service communication. For more information on maturity requirements for each level, please visit the CNCF Graduation Criteria.
To learn more about Microcks, visit microcks.io, explore the GitHub repository, or join the community on Discord.
The Publishing Industry in the AI Era: Why Bot Strategy is Now a Business Strategy
Kubernetes v1.36: Server-Side Sharded List and Watch
As Kubernetes clusters grow to tens of thousands of nodes, controllers that watch high-cardinality resources like Pods face a scaling wall. Every replica of a horizontally scaled controller receives the full stream of events from the API server, paying the CPU, memory, and network cost to deserialize everything, only to discard the objects it is not responsible for. Scaling out the controller does not reduce per-replica cost; it multiplies it.
Kubernetes v1.36 introduces server-side sharded list and watch as an alpha feature (KEP-5866). With this feature enabled, the API server filters events at the source so that each controller replica receives only the slice of the resource collection it owns.
The problem with client-side sharding
Some controllers, such as kube-state-metrics, already support horizontal sharding. Each replica is assigned a portion of the keyspace and discards objects that do not belong to it. While this works functionally, it does not reduce the volume of data flowing from the API server:
- N replicas x full event stream: every replica deserializes and processes every event, then throws away what it does not need.
- Network bandwidth scales with replicas, not with shard size.
- CPU spent on deserialization is wasted for the discarded fraction.
Server-side sharded list and watch solves this by moving the filtering upstream into the API server. Each replica tells the API server which hash range it owns, and the API server only sends matching events.
How it works
The feature adds a shardSelector field to ListOptions. Clients specify a
hash range using the shardRange() function:
shardRange(object.metadata.uid, '0x0000000000000000', '0x8000000000000000')
The API server computes a deterministic 64-bit
FNV-1a
hash of the specified field and returns only objects whose hash falls within the
range [start, end). This applies to both list responses and watch event
streams. The hash function produces the same result across all API server
instances, so the feature is safe to use with multiple API server replicas.
Currently supported field paths are object.metadata.uid and
object.metadata.namespace.
Using sharded watches in controllers
Controllers typically use informers to list and watch resources. To shard the
workload, each replica injects the shardSelector into the ListOptions used
by its informers via WithTweakListOptions:
import (
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/client-go/informers"
)
shardSelector := "shardRange(object.metadata.uid, '0x0000000000000000', '0x8000000000000000')"
factory := informers.NewSharedInformerFactoryWithOptions(client, resyncPeriod,
informers.WithTweakListOptions(func(opts *metav1.ListOptions) {
opts.ShardSelector = shardSelector
}),
)
For a 2-replica deployment, the selectors split the hash space in half:
// Replica 0: lower half of the hash space
"shardRange(object.metadata.uid, '0x0000000000000000', '0x8000000000000000')"
// Replica 1: upper half of the hash space
"shardRange(object.metadata.uid, '0x8000000000000000', '0x10000000000000000')"
A single replica can also cover non-contiguous ranges using ||:
"shardRange(object.metadata.uid, '0x0000000000000000', '0x4000000000000000') || " +
"shardRange(object.metadata.uid, '0x8000000000000000', '0xc000000000000000')"
Verifying server support
When the API server honors a shard selector, the list response includes a
shardInfo field in the response metadata that echoes back the applied
selector:
{
"kind": "PodList",
"apiVersion": "v1",
"metadata": {
"resourceVersion": "10245",
"shardInfo": {
"selector": "shardRange(object.metadata.uid, '0x0000000000000000', '0x8000000000000000')"
}
},
"items": [...]
}
If shardInfo is absent, the server did not honor the shard selector and the
client received the complete, unfiltered collection. In this case, the client
should be prepared to handle the full result set, for example by applying
client-side filtering to discard objects outside its assigned shard range.
Getting involved
This feature is in alpha and requires enabling the ShardedListAndWatch feature
gate on the API server. We are looking for feedback from controller authors and
operators running large clusters.
If you have questions or feedback, join the #sig-api-machinery channel on
Kubernetes Slack.
Rowhammer Attack Against NVIDIA Chips
A new rowhammer attack gives complete control of NVIDIA CPUs.
On Thursday, two research teams, working independently of each other, demonstrated attacks against two cards from Nvidia’s Ampere generation that take GPU rowhammering into new—and potentially much more consequential—territory: GDDR bitflips that give adversaries full control of CPU memory, resulting in full system compromise of the host machine. For the attack to work, IOMMU memory management must be disabled, as is the default in BIOS settings.
“Our work shows that Rowhammer, which is well-studied on CPUs, is a serious threat on GPUs as well,” said Andrew Kwong, co-author of one of the papers. “...
CVE-2026-31431: How Red Hat Advanced Cluster Security and Red Hat Advanced Cluster Management can help
Accelerate innovation and govern integrity with Red Hat Satellite 6.19
SBOMscanner 0.11.0 release
Kubernetes v1.36: Declarative Validation Graduates to GA
In Kubernetes v1.36, Declarative Validation for Kubernetes native types has reached General Availability (GA).
For users, this means more reliable, predictable, and better-documented APIs. By moving to a declarative model, the project also unlocks the future ability to publish validation rules via OpenAPI and integrate with ecosystem tools like Kubebuilder. For contributors and ecosystem developers, this replaces thousands of lines of handwritten validation code with a unified, maintainable framework.
This post covers why this migration was necessary, how the declarative validation framework works, and what new capabilities come with this GA release.
The Motivation: Escaping the "Handwritten" Technical Debt
For years, the validation of Kubernetes native APIs relied almost entirely on handwritten Go code. If a field needed to be bounded by a minimum value, or if two fields needed to be mutually exclusive, developers had to write explicit Go functions to enforce those constraints.
As the Kubernetes API surface expanded, this approach led to several systemic issues:
- Technical Debt: The project accumulated roughly 18,000 lines of boilerplate validation code. This code was difficult to maintain, error-prone, and required intense scrutiny during code reviews.
- Inconsistency: Without a centralized framework, validation rules were sometimes applied inconsistently across different resources.
- Opaque APIs: Handwritten validation logic was difficult to discover or analyze programmatically. This meant clients and tooling couldn't predictably know validation rules without consulting the source code or encountering errors at runtime.
The solution proposed by SIG API Machinery was Declarative Validation: using Interface Definition Language (IDL) tags (specifically +k8s: marker tags) directly within types.go files to define validation rules.
Enter validation-gen
At the core of the declarative validation feature is a new code generator called validation-gen. Just as Kubernetes uses generators for deep copies, conversions, and defaulting, validation-gen parses +k8s: tags and automatically generates the corresponding Go validation functions.
These generated functions are then registered seamlessly with the API scheme. The generator is designed as an extensible framework, allowing developers to plug in new "Validators" by describing the tags they parse and the Go logic they should produce.
A Comprehensive Suite of +k8s: Tags
The declarative validation framework introduces a comprehensive suite of marker tags that provide rich validation capabilities highly optimized for Go types. For a full list of supported tags, check out the official documentation. Here is a catalog of some of the most common tags you will now see in the Kubernetes codebase:
- Presence:
+k8s:optional,+k8s:required - Basic Constraints:
+k8s:minimum=0,+k8s:maximum=100,+k8s:maxLength=16,+k8s:format=k8s-short-name - Collections:
+k8s:listType=map,+k8s:listMapKey=type - Unions:
+k8s:unionMember,+k8s:unionDiscriminator - Immutability:
+k8s:immutable,+k8s:update=[NoSet, NoModify, NoClear]
Example Usage:
type ReplicationControllerSpec struct {
// +k8s:optional
// +k8s:minimum=0
Replicas *int32 `json:"replicas,omitempty"`
}
By placing these tags directly above the field definitions, the constraints are self-documenting and immediately visible to anyone reading the type definitions.
Advanced Capabilities: "Ambient Ratcheting"
One of the most substantial outcomes of this work is that validation ratcheting is now a standard, ambient part of the API. In the past, if we needed to tighten validation, we had to first add handwritten ratcheting code, wait a release, and then tighten the validation to avoid breaking existing objects.
With declarative validation, this safety mechanism is built-in. If a user updates an existing object, the validation framework compares the incoming object with the oldObject. If a specific field's value is semantically equivalent to its prior state (i.e., the user didn't change it), the new validation rule is bypassed. This "ambient ratcheting" means we can loosen or tighten validation immediately and in the least disruptive way possible.
Scaling API Reviews with kube-api-linter
Reaching GA required absolute confidence in the generated code, but our vision extends beyond just validation. Declarative validation is a key part of a comprehensive approach to making API review easier, more consistent, and highly scalable.
By moving validation rules out of opaque Go functions and into structured markers, we are empowering tools like kube-api-linter. This linter can now statically analyze API types and enforce API conventions automatically, significantly reducing the manual burden on SIG API Machinery reviewers and providing immediate feedback to contributors.
What's next?
With the release of Kubernetes v1.36, Declarative Validation graduates to General Availability (GA). As a stable feature, the associated DeclarativeValidation feature gate is now enabled by default. It has become the primary mechanism for adding new validation rules to Kubernetes native types.
Looking forward, the project is committed to adopting declarative validation even more extensively. This includes migrating the remaining legacy handwritten validation code for established APIs and requiring its use for all new APIs and new fields. This ongoing transition will continue to shrink the codebase's complexity while enhancing the consistency and reliability of the entire Kubernetes API surface.
Beyond the core migration, declarative validation also unlocks an exciting future for the broader ecosystem. Because validation rules are now defined as structured markers rather than opaque Go code, they can be parsed and reflected in the OpenAPI schemas published by the Kubernetes API server. This paves the way for tools like kubectl, client libraries, and IDEs to perform rich client-side validation before a request is ever sent to the cluster. The same declarative framework can also be consumed by ecosystem tools like Kubebuilder, enabling a more consistent developer experience for authors of Custom Resource Definitions (CRDs).
Getting involved
The migration to declarative validation is an ongoing effort. While the framework itself is GA, there is still work to be done migrating older APIs to the new declarative format.
If you are interested in contributing to the core of Kubernetes API Machinery, this is a fantastic place to start. Check out the validation-gen documentation, look for issues tagged with sig/api-machinery, and join the conversation in the #sig-api-machinery and #sig-api-machinery-dev-tools channels on Kubernetes Slack (for an invitation, visit https://slack.k8s.io/). You can also attend the SIG API Machinery meetings to get involved directly.
Acknowledgments
A huge thank you to everyone who helped bring this feature to GA:
- Tim Hockin
- Joe Betz
- Aaron Prindle
- Lalit Chauhan
- David Eads
- Darshan Murthy
- Jordan Liggitt
- Patrick Ohly
- Maciej Szulik
- Wojciech Tyczynski
- Joel Speed
- Bryce Palmer
And the many others across the Kubernetes community who contributed along the way.
Welcome to the declarative future of Kubernetes validation!
Announcing Kyverno release 1.18!
We’re excited to announce the release of Kyverno 1.18, our first release since graduating within the Cloud Native Computing Foundation.
This release builds on Kyverno’s growing role as a Kubernetes-native policy engine, with major investments in security, CLI capabilities, and policy engine reliability. It also continues our transition toward CEL-based policy types, setting the foundation for the future of policy as code.
TL;DR
Kyverno 1.18 delivers:
- Stronger security controls for HTTP-based policy execution and multiple CVE mitigations
- Significant CLI enhancements for testing and applying modern policy types
- Policy engine improvements for performance, observability, and scalability
- Enhancements to the policies Helm chart for better customization
There are no breaking changes in this release, but ClusterPolicy deprecation remains on track, and users should begin migrating to the newer policy types.
Security improvements
Security is a core pillar of Kyverno, and 1.18 introduces important safeguards for policy execution.
Safer HTTP execution
Kyverno policies can call external services via HTTP CEL libraries. In 1.18, this capability is significantly hardened:
- Blocklist/allowlist enforcement: by default, unsafe addresses like loopback and metadata services are blocked. Users can configure an allow list and a block list for cluster-scoped and namespaced policies. Additionally, HTTP calls from namespaced policies are default disabled, and need to be explicitly enabled using configuration flags. These changes help prevent SSRF-style abuse. See CVE-2026-4789 for details.
- Scoped token authorization: Previously, Kyverno HTTP calls included a token which could be used to impersonate Kyverno controllers. Now, HTTP calls include a separate scoped token that ensures that servers cannot misuse the token. See CVE-2026-41323 for details.
These changes reduce the risk of unintended external access while maintaining flexibility for advanced policy use cases.
CLI expansion and developer experience
Kyverno’s CLI continues to evolve as a critical tool for policy development and testing.
Expanded policy support
The kyverno apply and kyverno test commands now support:
- Cleanup policies
- HTTP and Envoy authorization policies
mutateExistingrules in MutatingPolicy- The
--exceptions-with-policiesflag for improved testing workflows
This significantly improves the ability to test modern policy types locally and in CI pipelines.
Reliability and usability improvements
Numerous fixes address:
- Error handling and reporting
- CRD compatibility without cluster connections
- Stability issues such as panics and file handle leaks
The result is a more predictable and developer-friendly experience when working with policies.
Policy engine improvements
Kyverno 1.18 includes several enhancements that improve how policies are executed and managed at scale.
Fine-grained success event filtering
A new successEventActions ConfigMap parameter allows users to control:
- Which success events are emitted
- How noisy or quiet policy reporting should be
This is especially valuable in large environments where event volume needs to be tuned.
Performance and scalability
Key improvements include:
- Memory-based HPA autoscaling for the admission controller
- TLS support on the /metrics endpoint
- Improved concurrency handling and reduced risk of race conditions
These changes make Kyverno more resilient in high-scale production environments.
CEL and policy execution enhancements
- Addition of a gzip CEL library for more advanced expressions
- Improved compilation and evaluation of policy variables and conditions
- Better alignment between policy types and execution engines
Image verification improvements
Several targeted improvements land for image verification:
- For
ClusterPolicies,imageRegistryCredentials.secretsnow accepts a namespace/name notation, and pod-levelimagePullSecretsare automatically used as registry credentials, useful in multi-tenant environments where each namespace manages its own pull secrets. - Reliability fixes for
ImageValidatingPolicy, including better handling of signed timestamps and TSA certificate chains, Notary resolver fixes, correctmatchImageReferencesfiltering, and improved autogen support for namespaced policies.
Policies Helm chart enhancements
The policies Helm chart continues to evolve with better customization and control.
New capabilities include:
- Support for excludes in
ValidatingPolicies(namespace, subject, resource rules, match conditions) auditAnnotationconfiguration- Per-policy annotation overrides
These improvements make it easier to tailor policies to specific organizational and operational needs.
Updated support policy
As Kyverno continues to grow in adoption, contributions, and overall project scope, we are evolving how we provide release support.
Starting with the 1.18 release, Kyverno will follow a “main + 1” patch support model.
This means:
- The current release (main) and the immediately previous release will be supported for patches. Patches are limited to critical and high severity CVEs, and other critical fixes. This provides roughly 3 months of community patch support.
- Older versions will no longer receive regular updates or fixes
Why this change
This adjustment allows the maintainer team to:
- Efficiently manage the AI driven increase in security issues and PRs
- Maintain higher standards for security and responsiveness
- Focus efforts on current and actively used versions
- Keep the project sustainable and manageable as it scales
What this means for users
We recommend that users:
- Stay up to date with recent Kyverno releases
- Plan upgrades in alignment with the 3 month support window, or use a commercial distribution that provides higher SLAs and long term support
- Reach out to the community if guidance is needed
This change ensures we can continue to deliver a secure, stable, and forward-moving project for everyone.
ClusterPolicy deprecation reminder
As a reminder, ClusterPolicy resources are planned for deprecation later this year.
We strongly encourage users to begin migrating to the newer policy types:
- ValidatingPolicy
- MutatingPolicy
- GeneratingPolicy
- ImageValidatingPolicy
- DeletingPolicy
What you should do
- Start migrating existing policies
- Test thoroughly using the CLI
- Report any gaps or issues
Community feedback is essential to ensuring a smooth transition and full feature parity. We ask that you please report issues and help us build full parity in the upcoming months.
Community updates
Kyverno’s graduation within the CNCF marks a major milestone for the project and its community.
Join the community
Kyverno community meetings now run at multiple global-friendly times:
- APAC / EU: Every other Wednesday 9:00 CET / India 13:30h / EU: 09:00h / Singapore: 16:00h / Australia: 18:00h
- USA/LATAM: Every other Wednesday 16:00 CET / India 20:30h / EU: 16:00h / NYC: 10:00h / SF: 7:00h
You can find all meetings on the CNCF Calendar using the Kyverno filter.
Additionally, we are working to create a space where community members can publish case studies and use cases to our community blog in hopes that this will serve as a space where everyone can learn from each other. Please keep an eye out for the announcements of when this section of the blog will be live and if you would like to submit a use case or case study, please reach out to [email protected] directly.
Getting started and upgrading
Kyverno 1.18 has no breaking changes, making it a safe and straightforward upgrade for most users.
Upgrade
- Review the release notes
- Test in staging environments
- Follow upgrade guidance in the documentation
Install
Install via the Kyverno website
Release Notes
What’s next
Looking ahead, the Kyverno roadmap focuses on:
- Continued investment in CEL-based policy types
- Improved policy authoring experience
- Scaling policy across multi-cluster environments
- Expanding into AI governance and policy-driven automation
Conclusion
Kyverno 1.18 is a meaningful step forward following our CNCF graduation.
With stronger security, expanded CLI capabilities, and continued investment in policy engine reliability and Kubernetes-native policy, Kyverno is helping teams move from policy enforcement to policy-driven operations at scale.
As the project continues to grow, we are also evolving how we operate to ensure long-term sustainability. Our move to an N-1 support model reflects a commitment to maintaining high-quality releases while keeping pace with the needs of a rapidly expanding community and ecosystem.
Upgrade to Kyverno 1.18, stay current with supported releases, begin your migration to the new policy types, and help us build the future of policy as code.
DarkSword Malware
DarkSword is a sophisticated piece of malware—probably government designed—that targets iOS.
Google Threat Intelligence Group (GTIG) has identified a new iOS full-chain exploit that leveraged multiple zero-day vulnerabilities to fully compromise devices. Based on toolmarks in recovered payloads, we believe the exploit chain to be called DarkSword. Since at least November 2025, GTIG has observed multiple commercial surveillance vendors and suspected state-sponsored actors utilizing DarkSword in distinct campaigns. These threat actors have deployed the exploit chain against targets in Saudi Arabia, Turkey, Malaysia, and Ukraine...
When AI finds the bugs: Why defense in depth was always the answer
Kubernetes v1.36: Admission Policies That Can't Be Deleted
If you've ever tried to enforce a security policy across a fleet of Kubernetes clusters, you've probably run into a frustrating chicken-and-egg problem. Your admission policies are API objects, which means they don't exist until someone creates them, and they can be deleted by anyone with the right permissions. There's always a window during cluster bootstrap where your policies aren't active yet, and there's no way to prevent a privileged user from removing them.
Kubernetes v1.36 introduces an alpha feature that addresses this: manifest-based admission control. It lets you define admission webhooks and CEL-based policies as files on disk, loaded by the API server at startup, before it serves any requests.
The gap we're closing
Most Kubernetes policy enforcement today works through the API. You create a ValidatingAdmissionPolicy or a webhook configuration as an API object, and the admission controller picks it up. This works well in steady state, but it has some fundamental limitations.
During cluster bootstrap, there's a gap between when the API server starts serving requests and when your policies are created and active. If you're restoring from a backup or recovering from an etcd failure, that gap can be significant.
There's also a self-protection problem. Admission webhooks and policies can't intercept operations on their own configuration resources. Kubernetes skips invoking webhooks on types like ValidatingWebhookConfiguration to avoid circular dependencies. That means a sufficiently privileged user can delete your critical admission policies, and there's nothing in the admission chain to stop them.
We - Kubernetes SIG API Machinery - wanted a way to say "these policies are always on, full stop."
How it works
You add a staticManifestsDir field to the AdmissionConfiguration file
that you already pass to the API server via --admission-control-config-file.
Point it at a directory, drop your policy YAML files in there, and the API
server loads them before it starts serving.
apiVersion: apiserver.config.k8s.io/v1
kind: AdmissionConfiguration
plugins:
- name: ValidatingAdmissionPolicy
configuration:
apiVersion: apiserver.config.k8s.io/v1
kind: ValidatingAdmissionPolicyConfiguration
staticManifestsDir: "/etc/kubernetes/admission/validating-policies/"
The manifest files are standard Kubernetes resource definitions. The only
requirement is that all the objects that these manifests define must have names ending in .static.k8s.io.
This reserved suffix prevents collisions with API-based configurations and
makes it easy to tell where an admission decision came from when you're
looking at metrics or audit logs.
Here's a complete example that denies privileged containers outside kube-system:
apiVersion: admissionregistration.k8s.io/v1
kind: ValidatingAdmissionPolicy
metadata:
name: "deny-privileged.static.k8s.io"
annotations:
kubernetes.io/description: "Deny launching privileged pods, anywhere this policy is applied"
spec:
failurePolicy: Fail
matchConstraints:
resourceRules:
- apiGroups: [""]
apiVersions: ["v1"]
operations: ["CREATE", "UPDATE"]
resources: ["pods"]
variables:
- name: allContainers
expression: >-
object.spec.containers +
(has(object.spec.initContainers) ? object.spec.initContainers : []) +
(has(object.spec.ephemeralContainers) ? object.spec.ephemeralContainers : [])
validations:
- expression: >-
!variables.allContainers.exists(c,
has(c.securityContext) && has(c.securityContext.privileged) &&
c.securityContext.privileged == true)
message: "Privileged containers are not allowed"
---
apiVersion: admissionregistration.k8s.io/v1
kind: ValidatingAdmissionPolicyBinding
metadata:
name: "deny-privileged-binding.static.k8s.io"
annotations:
kubernetes.io/description: "Bind deny-privileged policy to all namespaces except kube-system"
spec:
policyName: "deny-privileged.static.k8s.io"
validationActions:
- Deny
matchResources:
namespaceSelector:
matchExpressions:
- key: "kubernetes.io/metadata.name"
operator: NotIn
values: ["kube-system"]
Protecting what couldn't be protected before
The part we're most excited about is the ability to intercept operations on admission configuration resources themselves.
With API-based admission, webhooks and policies are never invoked on types like ValidatingAdmissionPolicy or ValidatingWebhookConfiguration. That restriction exists for good reason: if a webhook could reject changes to its own configuration, you could end up locked out with no way to fix it through the API.
Manifest-based policies don't have that problem. If a bad policy is blocking something it shouldn't, you fix the file on disk and the API server picks up the change. There's no circular dependency because the recovery path doesn't go through the API.
This means you can write a manifest-based policy that prevents deletion of your critical API-based admission policies. For platform teams managing shared clusters, this is a significant improvement. You can now guarantee that your baseline security policies can't be removed by a cluster admin, accidentally or otherwise.
Here's what that looks like in practice. This policy prevents any
modification or deletion of admission resources that carry the
platform.example.com/protected: "true" label:
apiVersion: admissionregistration.k8s.io/v1
kind: ValidatingAdmissionPolicy
metadata:
name: "protect-policies.static.k8s.io"
annotations:
kubernetes.io/description: "Prevent modification or deletion of protected admission resources"
spec:
failurePolicy: Fail
matchConstraints:
resourceRules:
- apiGroups: ["admissionregistration.k8s.io"]
apiVersions: ["*"]
operations: ["DELETE", "UPDATE"]
resources:
- "validatingadmissionpolicies"
- "validatingadmissionpolicybindings"
- "validatingwebhookconfigurations"
- "mutatingwebhookconfigurations"
validations:
- expression: >-
!has(oldObject.metadata.labels) ||
!('platform.example.com/protected' in oldObject.metadata.labels) ||
oldObject.metadata.labels['platform.example.com/protected'] != 'true'
message: "Protected admission resources cannot be modified or deleted"
---
apiVersion: admissionregistration.k8s.io/v1
kind: ValidatingAdmissionPolicyBinding
metadata:
name: "protect-policies-binding.static.k8s.io"
annotations:
kubernetes.io/description: "Bind protect-policies policy to all admission resources"
spec:
policyName: "protect-policies.static.k8s.io"
validationActions:
- Deny
With this in place, any API-based admission policy or webhook configuration
labeled platform.example.com/protected: "true" is shielded from tampering.
The protection itself lives on disk and can't be removed through the API.
A few things to know
Manifest-based configurations are intentionally self-contained. They can't
reference API resources, which means no paramKind for policies, no
Service references for admission webhooks (instead they are URL-only),
and bindings may only reference
policies in the same manifest set. These restrictions exist because the
configurations need to work without any cluster state, including at startup
before etcd is available.
If you run multiple API server instances, each one loads its own manifest files independently. There's no cross-server synchronization built in. This is the same model as other file-based API server configurations like encryption at rest. When this feature is enabled, Kubernetes exposes a configuration hash as a label on relevant metrics, so you can detect drift.
Files are watched for changes at runtime, so you don't need to restart the API server to update policies. If you update a manifest file, the API server validates the new configuration and swaps it in atomically. If validation fails, it keeps the previous good configuration and logs the error. This means you can roll out policy changes across your fleet using standard configuration management tools (Ansible, Puppet, or even mounted ConfigMaps) without any API server downtime.
The initial load at startup is stricter: if any manifest is invalid, the API server won't start. This is intentional. At startup, failing fast is safer than running without your expected policies.
Try it out
To try this in Kubernetes v1.36:
- Enable the
ManifestBasedAdmissionControlConfigfeature gate for each kube-apiserver. - Create a directory with your static manifest files. If you need to mount that in to the Pod where the API server runs, do that too. Read-only is fine.
- Configure
staticManifestsDirin yourAdmissionConfigurationwith the directory path. - Start the API server with
--admission-control-config-filepointing to yourAdmissionConfigurationfile.
The full documentation is at Manifest-Based Admission Control, and you can follow KEP-5793 for ongoing progress.
We'd love to hear your feedback. Reach out on the #sig-api-machinery channel on Kubernetes Slack (for an invitation, visit https://slack.k8s.io/).
How to get involved
If you're interested in contributing to this feature or other SIG API Machinery projects, join us on #sig-api-machinery on Kubernetes Slack. You're also welcome to attend the SIG API Machinery meetings, held every other Wednesday.
Kubernetes v1.36: Admission Policies That Can't Be Deleted
If you've ever tried to enforce a security policy across a fleet of Kubernetes clusters, you've probably run into a frustrating chicken-and-egg problem. Your admission policies are API objects, which means they don't exist until someone creates them, and they can be deleted by anyone with the right permissions. There's always a window during cluster bootstrap where your policies aren't active yet, and there's no way to prevent a privileged user from removing them.
Kubernetes v1.36 introduces an alpha feature that addresses this: manifest-based admission control. It lets you define admission webhooks and CEL-based policies as files on disk, loaded by the API server at startup, before it serves any requests.
The gap we're closing
Most Kubernetes policy enforcement today works through the API. You create a ValidatingAdmissionPolicy or a webhook configuration as an API object, and the admission controller picks it up. This works well in steady state, but it has some fundamental limitations.
During cluster bootstrap, there's a gap between when the API server starts serving requests and when your policies are created and active. If you're restoring from a backup or recovering from an etcd failure, that gap can be significant.
There's also a self-protection problem. Admission webhooks and policies can't intercept operations on their own configuration resources. Kubernetes skips invoking webhooks on types like ValidatingWebhookConfiguration to avoid circular dependencies. That means a sufficiently privileged user can delete your critical admission policies, and there's nothing in the admission chain to stop them.
We - Kubernetes SIG API Machinery - wanted a way to say "these policies are always on, full stop."
How it works
You add a staticManifestsDir field to the AdmissionConfiguration file
that you already pass to the API server via --admission-control-config-file.
Point it at a directory, drop your policy YAML files in there, and the API
server loads them before it starts serving.
apiVersion: apiserver.config.k8s.io/v1
kind: AdmissionConfiguration
plugins:
- name: ValidatingAdmissionPolicy
configuration:
apiVersion: apiserver.config.k8s.io/v1
kind: ValidatingAdmissionPolicyConfiguration
staticManifestsDir: "/etc/kubernetes/admission/validating-policies/"
The manifest files are standard Kubernetes resource definitions. The only
requirement is that all the objects that these manifests define must have names ending in .static.k8s.io.
This reserved suffix prevents collisions with API-based configurations and
makes it easy to tell where an admission decision came from when you're
looking at metrics or audit logs.
Here's a complete example that denies privileged containers outside kube-system:
apiVersion: admissionregistration.k8s.io/v1
kind: ValidatingAdmissionPolicy
metadata:
name: "deny-privileged.static.k8s.io"
annotations:
kubernetes.io/description: "Deny launching privileged pods, anywhere this policy is applied"
spec:
failurePolicy: Fail
matchConstraints:
resourceRules:
- apiGroups: [""]
apiVersions: ["v1"]
operations: ["CREATE", "UPDATE"]
resources: ["pods"]
variables:
- name: allContainers
expression: >-
object.spec.containers +
(has(object.spec.initContainers) ? object.spec.initContainers : []) +
(has(object.spec.ephemeralContainers) ? object.spec.ephemeralContainers : [])
validations:
- expression: >-
!variables.allContainers.exists(c,
has(c.securityContext) && has(c.securityContext.privileged) &&
c.securityContext.privileged == true)
message: "Privileged containers are not allowed"
---
apiVersion: admissionregistration.k8s.io/v1
kind: ValidatingAdmissionPolicyBinding
metadata:
name: "deny-privileged-binding.static.k8s.io"
annotations:
kubernetes.io/description: "Bind deny-privileged policy to all namespaces except kube-system"
spec:
policyName: "deny-privileged.static.k8s.io"
validationActions:
- Deny
matchResources:
namespaceSelector:
matchExpressions:
- key: "kubernetes.io/metadata.name"
operator: NotIn
values: ["kube-system"]
Protecting what couldn't be protected before
The part we're most excited about is the ability to intercept operations on admission configuration resources themselves.
With API-based admission, webhooks and policies are never invoked on types like ValidatingAdmissionPolicy or ValidatingWebhookConfiguration. That restriction exists for good reason: if a webhook could reject changes to its own configuration, you could end up locked out with no way to fix it through the API.
Manifest-based policies don't have that problem. If a bad policy is blocking something it shouldn't, you fix the file on disk and the API server picks up the change. There's no circular dependency because the recovery path doesn't go through the API.
This means you can write a manifest-based policy that prevents deletion of your critical API-based admission policies. For platform teams managing shared clusters, this is a significant improvement. You can now guarantee that your baseline security policies can't be removed by a cluster admin, accidentally or otherwise.
Here's what that looks like in practice. This policy prevents any
modification or deletion of admission resources that carry the
platform.example.com/protected: "true" label:
apiVersion: admissionregistration.k8s.io/v1
kind: ValidatingAdmissionPolicy
metadata:
name: "protect-policies.static.k8s.io"
annotations:
kubernetes.io/description: "Prevent modification or deletion of protected admission resources"
spec:
failurePolicy: Fail
matchConstraints:
resourceRules:
- apiGroups: ["admissionregistration.k8s.io"]
apiVersions: ["*"]
operations: ["DELETE", "UPDATE"]
resources:
- "validatingadmissionpolicies"
- "validatingadmissionpolicybindings"
- "validatingwebhookconfigurations"
- "mutatingwebhookconfigurations"
validations:
- expression: >-
!has(oldObject.metadata.labels) ||
!('platform.example.com/protected' in oldObject.metadata.labels) ||
oldObject.metadata.labels['platform.example.com/protected'] != 'true'
message: "Protected admission resources cannot be modified or deleted"
---
apiVersion: admissionregistration.k8s.io/v1
kind: ValidatingAdmissionPolicyBinding
metadata:
name: "protect-policies-binding.static.k8s.io"
annotations:
kubernetes.io/description: "Bind protect-policies policy to all admission resources"
spec:
policyName: "protect-policies.static.k8s.io"
validationActions:
- Deny
With this in place, any API-based admission policy or webhook configuration
labeled platform.example.com/protected: "true" is shielded from tampering.
The protection itself lives on disk and can't be removed through the API.
A few things to know
Manifest-based configurations are intentionally self-contained. They can't
reference API resources, which means no paramKind for policies, no
Service references for admission webhooks (instead they are URL-only),
and bindings may only reference
policies in the same manifest set. These restrictions exist because the
configurations need to work without any cluster state, including at startup
before etcd is available.
If you run multiple API server instances, each one loads its own manifest files independently. There's no cross-server synchronization built in. This is the same model as other file-based API server configurations like encryption at rest. When this feature is enabled, Kubernetes exposes a configuration hash as a label on relevant metrics, so you can detect drift.
Files are watched for changes at runtime, so you don't need to restart the API server to update policies. If you update a manifest file, the API server validates the new configuration and swaps it in atomically. If validation fails, it keeps the previous good configuration and logs the error. This means you can roll out policy changes across your fleet using standard configuration management tools (Ansible, Puppet, or even mounted ConfigMaps) without any API server downtime.
The initial load at startup is stricter: if any manifest is invalid, the API server won't start. This is intentional. At startup, failing fast is safer than running without your expected policies.
Try it out
To try this in Kubernetes v1.36:
- Enable the
ManifestBasedAdmissionControlConfigfeature gate for each kube-apiserver. - Create a directory with your static manifest files. If you need to mount that in to the Pod where the API server runs, do that too. Read-only is fine.
- Configure
staticManifestsDirin yourAdmissionConfigurationwith the directory path. - Start the API server with
--admission-control-config-filepointing to yourAdmissionConfigurationfile.
The full documentation is at Manifest-Based Admission Control, and you can follow KEP-5793 for ongoing progress.
We'd love to hear your feedback. Reach out on the #sig-api-machinery channel on Kubernetes Slack (for an invitation, visit https://slack.k8s.io/).
How to get involved
If you're interested in contributing to this feature or other SIG API Machinery projects, join us on #sig-api-machinery on Kubernetes Slack. You're also welcome to attend the SIG API Machinery meetings, held every other Wednesday.
Kubernetes v1.36: Admission Policies That Can't Be Deleted
If you've ever tried to enforce a security policy across a fleet of Kubernetes clusters, you've probably run into a frustrating chicken-and-egg problem. Your admission policies are API objects, which means they don't exist until someone creates them, and they can be deleted by anyone with the right permissions. There's always a window during cluster bootstrap where your policies aren't active yet, and there's no way to prevent a privileged user from removing them.
Kubernetes v1.36 introduces an alpha feature that addresses this: manifest-based admission control. It lets you define admission webhooks and CEL-based policies as files on disk, loaded by the API server at startup, before it serves any requests.
The gap we're closing
Most Kubernetes policy enforcement today works through the API. You create a ValidatingAdmissionPolicy or a webhook configuration as an API object, and the admission controller picks it up. This works well in steady state, but it has some fundamental limitations.
During cluster bootstrap, there's a gap between when the API server starts serving requests and when your policies are created and active. If you're restoring from a backup or recovering from an etcd failure, that gap can be significant.
There's also a self-protection problem. Admission webhooks and policies can't intercept operations on their own configuration resources. Kubernetes skips invoking webhooks on types like ValidatingWebhookConfiguration to avoid circular dependencies. That means a sufficiently privileged user can delete your critical admission policies, and there's nothing in the admission chain to stop them.
We - Kubernetes SIG API Machinery - wanted a way to say "these policies are always on, full stop."
How it works
You add a staticManifestsDir field to the AdmissionConfiguration file
that you already pass to the API server via --admission-control-config-file.
Point it at a directory, drop your policy YAML files in there, and the API
server loads them before it starts serving.
apiVersion: apiserver.config.k8s.io/v1
kind: AdmissionConfiguration
plugins:
- name: ValidatingAdmissionPolicy
configuration:
apiVersion: apiserver.config.k8s.io/v1
kind: ValidatingAdmissionPolicyConfiguration
staticManifestsDir: "/etc/kubernetes/admission/validating-policies/"
The manifest files are standard Kubernetes resource definitions. The only
requirement is that all the objects that these manifests define must have names ending in .static.k8s.io.
This reserved suffix prevents collisions with API-based configurations and
makes it easy to tell where an admission decision came from when you're
looking at metrics or audit logs.
Here's a complete example that denies privileged containers outside kube-system:
apiVersion: admissionregistration.k8s.io/v1
kind: ValidatingAdmissionPolicy
metadata:
name: "deny-privileged.static.k8s.io"
annotations:
kubernetes.io/description: "Deny launching privileged pods, anywhere this policy is applied"
spec:
failurePolicy: Fail
matchConstraints:
resourceRules:
- apiGroups: [""]
apiVersions: ["v1"]
operations: ["CREATE", "UPDATE"]
resources: ["pods"]
variables:
- name: allContainers
expression: >-
object.spec.containers +
(has(object.spec.initContainers) ? object.spec.initContainers : []) +
(has(object.spec.ephemeralContainers) ? object.spec.ephemeralContainers : [])
validations:
- expression: >-
!variables.allContainers.exists(c,
has(c.securityContext) && has(c.securityContext.privileged) &&
c.securityContext.privileged == true)
message: "Privileged containers are not allowed"
---
apiVersion: admissionregistration.k8s.io/v1
kind: ValidatingAdmissionPolicyBinding
metadata:
name: "deny-privileged-binding.static.k8s.io"
annotations:
kubernetes.io/description: "Bind deny-privileged policy to all namespaces except kube-system"
spec:
policyName: "deny-privileged.static.k8s.io"
validationActions:
- Deny
matchResources:
namespaceSelector:
matchExpressions:
- key: "kubernetes.io/metadata.name"
operator: NotIn
values: ["kube-system"]
Protecting what couldn't be protected before
The part we're most excited about is the ability to intercept operations on admission configuration resources themselves.
With API-based admission, webhooks and policies are never invoked on types like ValidatingAdmissionPolicy or ValidatingWebhookConfiguration. That restriction exists for good reason: if a webhook could reject changes to its own configuration, you could end up locked out with no way to fix it through the API.
Manifest-based policies don't have that problem. If a bad policy is blocking something it shouldn't, you fix the file on disk and the API server picks up the change. There's no circular dependency because the recovery path doesn't go through the API.
This means you can write a manifest-based policy that prevents deletion of your critical API-based admission policies. For platform teams managing shared clusters, this is a significant improvement. You can now guarantee that your baseline security policies can't be removed by a cluster admin, accidentally or otherwise.
Here's what that looks like in practice. This policy prevents any
modification or deletion of admission resources that carry the
platform.example.com/protected: "true" label:
apiVersion: admissionregistration.k8s.io/v1
kind: ValidatingAdmissionPolicy
metadata:
name: "protect-policies.static.k8s.io"
annotations:
kubernetes.io/description: "Prevent modification or deletion of protected admission resources"
spec:
failurePolicy: Fail
matchConstraints:
resourceRules:
- apiGroups: ["admissionregistration.k8s.io"]
apiVersions: ["*"]
operations: ["DELETE", "UPDATE"]
resources:
- "validatingadmissionpolicies"
- "validatingadmissionpolicybindings"
- "validatingwebhookconfigurations"
- "mutatingwebhookconfigurations"
validations:
- expression: >-
!has(oldObject.metadata.labels) ||
!('platform.example.com/protected' in oldObject.metadata.labels) ||
oldObject.metadata.labels['platform.example.com/protected'] != 'true'
message: "Protected admission resources cannot be modified or deleted"
---
apiVersion: admissionregistration.k8s.io/v1
kind: ValidatingAdmissionPolicyBinding
metadata:
name: "protect-policies-binding.static.k8s.io"
annotations:
kubernetes.io/description: "Bind protect-policies policy to all admission resources"
spec:
policyName: "protect-policies.static.k8s.io"
validationActions:
- Deny
With this in place, any API-based admission policy or webhook configuration
labeled platform.example.com/protected: "true" is shielded from tampering.
The protection itself lives on disk and can't be removed through the API.
A few things to know
Manifest-based configurations are intentionally self-contained. They can't
reference API resources, which means no paramKind for policies, no
Service references for admission webhooks (instead they are URL-only),
and bindings may only reference
policies in the same manifest set. These restrictions exist because the
configurations need to work without any cluster state, including at startup
before etcd is available.
If you run multiple API server instances, each one loads its own manifest files independently. There's no cross-server synchronization built in. This is the same model as other file-based API server configurations like encryption at rest. When this feature is enabled, Kubernetes exposes a configuration hash as a label on relevant metrics, so you can detect drift.
Files are watched for changes at runtime, so you don't need to restart the API server to update policies. If you update a manifest file, the API server validates the new configuration and swaps it in atomically. If validation fails, it keeps the previous good configuration and logs the error. This means you can roll out policy changes across your fleet using standard configuration management tools (Ansible, Puppet, or even mounted ConfigMaps) without any API server downtime.
The initial load at startup is stricter: if any manifest is invalid, the API server won't start. This is intentional. At startup, failing fast is safer than running without your expected policies.
Try it out
To try this in Kubernetes v1.36:
- Enable the
ManifestBasedAdmissionControlConfigfeature gate for each kube-apiserver. - Create a directory with your static manifest files. If you need to mount that in to the Pod where the API server runs, do that too. Read-only is fine.
- Configure
staticManifestsDirin yourAdmissionConfigurationwith the directory path. - Start the API server with
--admission-control-config-filepointing to yourAdmissionConfigurationfile.
The full documentation is at Manifest-Based Admission Control, and you can follow KEP-5793 for ongoing progress.
We'd love to hear your feedback. Reach out on the #sig-api-machinery channel on Kubernetes Slack (for an invitation, visit https://slack.k8s.io/).
How to get involved
If you're interested in contributing to this feature or other SIG API Machinery projects, join us on #sig-api-machinery on Kubernetes Slack. You're also welcome to attend the SIG API Machinery meetings, held every other Wednesday.
Hacking Polymarket
Polymarket is a platform where people can bet on real-world events, political and otherwise. Leaving the ethical considerations of this aside (for one, it facilitates assassination), one of the issues with making this work is the verification of these real-world events. Polymarket gamblers have threatened a journalist because his story was being used to verify an event. And now, gamblers are taking hair dryers to weather sensors to rig weather bets.
There’s also insider trading: a lot of it.
May 1 Security Release Patches RBAC Bypass in Transactions
SIG-etcd released updates v3.6.11, v3.5.30, and v3.4.44 today. These patch releases fix a vulnerability that allows an authenticated user to bypass RBAC authorization checks when reading data via PrevKv or attaching leases inside Put requests nested in etcd transactions.
In addition, v3.6.11 and v3.5.30 contain a bug fix for an issue that prevented adding a new member when one member was down, even though quorum was still satisfied.
This vulnerability does not affect etcd as a part of the Kubernetes Control Plane. Kubernetes does not rely on etcd’s built-in authentication and authorization; the API server handles authentication and authorization itself. The issue only affects etcd clusters in other contexts, specifically ones with Auth enabled where it is required for access control in untrusted or partially trusted networks or with untrusted users.
Kubernetes v1.36: Pod-Level Resource Managers (Alpha)
Kubernetes v1.36 introduces
Pod-Level Resource Managers
as an alpha feature, bringing a more flexible and powerful resource management
model to performance-sensitive workloads. This enhancement extends the kubelet's
Topology, CPU, and Memory Managers to support pod-level resource specifications
(.spec.resources), evolving them from a strictly per-container allocation
model to a pod-centric one.
Why do we need pod-level resource managers?
When running performance-critical workloads such as machine learning (ML) training, high-frequency trading applications, or low-latency databases, you often need exclusive, NUMA-aligned resources for your primary application containers to ensure predictable performance.
However, modern Kubernetes pods rarely consist of just one container. They frequently include sidecar containers for logging, monitoring, service meshes, or data ingestion.
Before this feature, this created a trade-off, to get NUMA-aligned, exclusive resources for your main application, you had to allocate exclusive, integer-based CPU resources to every container in the pod. This might be wasteful for lightweight sidecars. If you didn't do this, you forfeited the pod's Guaranteed Quality of Service (QoS) class entirely, losing the performance benefits.
Introducing pod-level resource managers
Enabling pod-level resources support for the resource managers (via the
PodLevelResourceManagers and PodLevelResources feature gates) allows the
kubelet to create hybrid resource allocation models. This brings flexibility
and efficiency to high-performance workloads without sacrificing NUMA alignment.
Real-world use cases
Here are a few practical scenarios demonstrating how this feature can be applied, depending on the configured Topology Manager scope:
1. Tightly-coupled database (Topology manager's pod scope)
Consider a latency-sensitive database pod that includes a main database container, a local metrics exporter, and a backup agent sidecar.
When configured with the pod Topology Manager scope, the kubelet performs a
single NUMA alignment based on the entire pod's budget. The database container
gets its exclusive CPU and memory slices from that NUMA node. The remaining
resources from the pod's budget form a new pod shared pool. The metrics
exporter and backup agent run in this pod shared pool. They share resources with
each other, but they are strictly isolated from the database's exclusive slices
and the rest of the node.
This allows you to safely co-locate auxiliary containers on the same NUMA node as your primary workload without wasting dedicated cores on them.
apiVersion: v1
kind: Pod
metadata:
name: tightly-coupled-database
spec:
# Pod-level resources establish the overall budget and NUMA alignment size.
resources:
requests:
cpu: "8"
memory: "16Gi"
limits:
cpu: "8"
memory: "16Gi"
initContainers:
- name: metrics-exporter
image: metrics-exporter:v1
restartPolicy: Always
- name: backup-agent
image: backup-agent:v1
restartPolicy: Always
containers:
- name: database
image: database:v1
# This Guaranteed container gets an exclusive 6 CPU slice from the pod's budget.
# The remaining 2 CPUs and 4Gi memory form the pod shared pool for the sidecars.
resources:
requests:
cpu: "6"
memory: "12Gi"
limits:
cpu: "6"
memory: "12Gi"
2. ML workload with infrastructure sidecars (Topology manager's container scope)
Imagine a pod running a GPU-accelerated ML training workload alongside a generic service mesh sidecar.
Under the container Topology Manager scope, the kubelet evaluates each
container individually. You can grant the ML container exclusive, NUMA-aligned
CPUs and Memory for maximum performance. Meanwhile, the service mesh sidecar
doesn't need to be NUMA-aligned; it can run in the general node-wide shared
pool. The collective resource consumption is still safely bounded by the overall
pod limits, but you only allocate NUMA-aligned, exclusive resources to the
specific containers that actually require them.
apiVersion: v1
kind: Pod
metadata:
name: ml-workload
spec:
# Pod-level resources establish the overall budget constraint.
resources:
requests:
cpu: "4"
memory: "8Gi"
limits:
cpu: "4"
memory: "8Gi"
initContainers:
- name: service-mesh-sidecar
image: service-mesh:v1
restartPolicy: Always
containers:
- name: ml-training
image: ml-training:v1
# Under the 'container' scope, this Guaranteed container receives exclusive,
# NUMA-aligned resources, while the sidecar runs in the node's shared pool.
resources:
requests:
cpu: "3"
memory: "6Gi"
limits:
cpu: "3"
memory: "6Gi"
CPU quotas (CFS) and isolation
When running these mixed workloads within a pod, isolation is enforced differently depending on the allocation:
- Exclusive containers: Containers granted exclusive CPU slices have their CPU CFS quota enforcement disabled at the container level, allowing them to run without being throttled by the Linux scheduler.
- Pod shared pool containers: Containers falling into the pod shared pool have CPU CFS quotas enforced at the pod level, ensuring they do not consume more than the leftover pod budget.
How to enable Pod-Level Resource Managers
Using this feature requires Kubernetes v1.36 or newer. To enable it, you must configure the kubelet with the appropriate feature gates and policies:
- Enable the
PodLevelResourcesandPodLevelResourceManagersfeature gates. - Configure the
Topology Manager
with a policy other than
none(i.e.,best-effort,restricted, orsingle-numa-node). - Set the
Topology Manager scope
to either
podorcontainerusing thetopologyManagerScopefield in theKubeletConfiguration. - Configure the
CPU Manager with
the
staticpolicy. - Configure the
Memory Manager with the
Staticpolicy.
Observability
To help cluster administrators monitor and debug these new allocation models, we have introduced several new kubelet metrics when the feature gate is enabled:
resource_manager_allocations_total: Counts the total number of exclusive resource allocations performed by a manager. Thesourcelabel ("pod" or "node") distinguishes between allocations drawn from the node-level pool versus a pre-allocated pod-level pool.resource_manager_allocation_errors_total: Counts errors encountered during exclusive resource allocation, distinguished by the intended allocationsource("pod" or "node").resource_manager_container_assignments: Tracks the cumulative number of containers running with specific assignment types. Theassignment_typelabel ("node_exclusive", "pod_exclusive", "pod_shared") provides visibility into how workloads are distributed.
Current limitations and caveats
While this feature opens up new possibilities, there are a few things to keep in mind during its alpha phase. Be sure to review the Limitations and caveats in the official documentation for full details on compatibility, requirements, and downgrade instructions.
Getting started and providing feedback
For a deep dive into the technical details and configuration of this feature, check out the official concept documentation:
To learn more about the overall pod-level resources feature and how to assign resources to pods, see:
As this feature moves through Alpha, your feedback is invaluable. Please report any issues or share your experiences via the standard Kubernetes communication channels:
Kubernetes v1.36: Pod-Level Resource Managers (Alpha)
Kubernetes v1.36 introduces
Pod-Level Resource Managers
as an alpha feature, bringing a more flexible and powerful resource management
model to performance-sensitive workloads. This enhancement extends the kubelet's
Topology, CPU, and Memory Managers to support pod-level resource specifications
(.spec.resources), evolving them from a strictly per-container allocation
model to a pod-centric one.
Why do we need pod-level resource managers?
When running performance-critical workloads such as machine learning (ML) training, high-frequency trading applications, or low-latency databases, you often need exclusive, NUMA-aligned resources for your primary application containers to ensure predictable performance.
However, modern Kubernetes pods rarely consist of just one container. They frequently include sidecar containers for logging, monitoring, service meshes, or data ingestion.
Before this feature, this created a trade-off, to get NUMA-aligned, exclusive resources for your main application, you had to allocate exclusive, integer-based CPU resources to every container in the pod. This might be wasteful for lightweight sidecars. If you didn't do this, you forfeited the pod's Guaranteed Quality of Service (QoS) class entirely, losing the performance benefits.
Introducing pod-level resource managers
Enabling pod-level resources support for the resource managers (via the
PodLevelResourceManagers and PodLevelResources feature gates) allows the
kubelet to create hybrid resource allocation models. This brings flexibility
and efficiency to high-performance workloads without sacrificing NUMA alignment.
Real-world use cases
Here are a few practical scenarios demonstrating how this feature can be applied, depending on the configured Topology Manager scope:
1. Tightly-coupled database (Topology manager's pod scope)
Consider a latency-sensitive database pod that includes a main database container, a local metrics exporter, and a backup agent sidecar.
When configured with the pod Topology Manager scope, the kubelet performs a
single NUMA alignment based on the entire pod's budget. The database container
gets its exclusive CPU and memory slices from that NUMA node. The remaining
resources from the pod's budget form a new pod shared pool. The metrics
exporter and backup agent run in this pod shared pool. They share resources with
each other, but they are strictly isolated from the database's exclusive slices
and the rest of the node.
This allows you to safely co-locate auxiliary containers on the same NUMA node as your primary workload without wasting dedicated cores on them.
apiVersion: v1
kind: Pod
metadata:
name: tightly-coupled-database
spec:
# Pod-level resources establish the overall budget and NUMA alignment size.
resources:
requests:
cpu: "8"
memory: "16Gi"
limits:
cpu: "8"
memory: "16Gi"
initContainers:
- name: metrics-exporter
image: metrics-exporter:v1
restartPolicy: Always
- name: backup-agent
image: backup-agent:v1
restartPolicy: Always
containers:
- name: database
image: database:v1
# This Guaranteed container gets an exclusive 6 CPU slice from the pod's budget.
# The remaining 2 CPUs and 4Gi memory form the pod shared pool for the sidecars.
resources:
requests:
cpu: "6"
memory: "12Gi"
limits:
cpu: "6"
memory: "12Gi"
2. ML workload with infrastructure sidecars (Topology manager's container scope)
Imagine a pod running a GPU-accelerated ML training workload alongside a generic service mesh sidecar.
Under the container Topology Manager scope, the kubelet evaluates each
container individually. You can grant the ML container exclusive, NUMA-aligned
CPUs and Memory for maximum performance. Meanwhile, the service mesh sidecar
doesn't need to be NUMA-aligned; it can run in the general node-wide shared
pool. The collective resource consumption is still safely bounded by the overall
pod limits, but you only allocate NUMA-aligned, exclusive resources to the
specific containers that actually require them.
apiVersion: v1
kind: Pod
metadata:
name: ml-workload
spec:
# Pod-level resources establish the overall budget constraint.
resources:
requests:
cpu: "4"
memory: "8Gi"
limits:
cpu: "4"
memory: "8Gi"
initContainers:
- name: service-mesh-sidecar
image: service-mesh:v1
restartPolicy: Always
containers:
- name: ml-training
image: ml-training:v1
# Under the 'container' scope, this Guaranteed container receives exclusive,
# NUMA-aligned resources, while the sidecar runs in the node's shared pool.
resources:
requests:
cpu: "3"
memory: "6Gi"
limits:
cpu: "3"
memory: "6Gi"
CPU quotas (CFS) and isolation
When running these mixed workloads within a pod, isolation is enforced differently depending on the allocation:
- Exclusive containers: Containers granted exclusive CPU slices have their CPU CFS quota enforcement disabled at the container level, allowing them to run without being throttled by the Linux scheduler.
- Pod shared pool containers: Containers falling into the pod shared pool have CPU CFS quotas enforced at the pod level, ensuring they do not consume more than the leftover pod budget.
How to enable Pod-Level Resource Managers
Using this feature requires Kubernetes v1.36 or newer. To enable it, you must configure the kubelet with the appropriate feature gates and policies:
- Enable the
PodLevelResourcesandPodLevelResourceManagersfeature gates. - Configure the
Topology Manager
with a policy other than
none(i.e.,best-effort,restricted, orsingle-numa-node). - Set the
Topology Manager scope
to either
podorcontainerusing thetopologyManagerScopefield in theKubeletConfiguration. - Configure the
CPU Manager with
the
staticpolicy. - Configure the
Memory Manager with the
Staticpolicy.
Observability
To help cluster administrators monitor and debug these new allocation models, we have introduced several new kubelet metrics when the feature gate is enabled:
resource_manager_allocations_total: Counts the total number of exclusive resource allocations performed by a manager. Thesourcelabel ("pod" or "node") distinguishes between allocations drawn from the node-level pool versus a pre-allocated pod-level pool.resource_manager_allocation_errors_total: Counts errors encountered during exclusive resource allocation, distinguished by the intended allocationsource("pod" or "node").resource_manager_container_assignments: Tracks the cumulative number of containers running with specific assignment types. Theassignment_typelabel ("node_exclusive", "pod_exclusive", "pod_shared") provides visibility into how workloads are distributed.
Current limitations and caveats
While this feature opens up new possibilities, there are a few things to keep in mind during its alpha phase. Be sure to review the Limitations and caveats in the official documentation for full details on compatibility, requirements, and downgrade instructions.
Getting started and providing feedback
For a deep dive into the technical details and configuration of this feature, check out the official concept documentation:
To learn more about the overall pod-level resources feature and how to assign resources to pods, see:
As this feature moves through Alpha, your feedback is invaluable. Please report any issues or share your experiences via the standard Kubernetes communication channels:
Kubernetes v1.36: Pod-Level Resource Managers (Alpha)
Kubernetes v1.36 introduces
Pod-Level Resource Managers
as an alpha feature, bringing a more flexible and powerful resource management
model to performance-sensitive workloads. This enhancement extends the kubelet's
Topology, CPU, and Memory Managers to support pod-level resource specifications
(.spec.resources), evolving them from a strictly per-container allocation
model to a pod-centric one.
Why do we need pod-level resource managers?
When running performance-critical workloads such as machine learning (ML) training, high-frequency trading applications, or low-latency databases, you often need exclusive, NUMA-aligned resources for your primary application containers to ensure predictable performance.
However, modern Kubernetes pods rarely consist of just one container. They frequently include sidecar containers for logging, monitoring, service meshes, or data ingestion.
Before this feature, this created a trade-off, to get NUMA-aligned, exclusive resources for your main application, you had to allocate exclusive, integer-based CPU resources to every container in the pod. This might be wasteful for lightweight sidecars. If you didn't do this, you forfeited the pod's Guaranteed Quality of Service (QoS) class entirely, losing the performance benefits.
Introducing pod-level resource managers
Enabling pod-level resources support for the resource managers (via the
PodLevelResourceManagers and PodLevelResources feature gates) allows the
kubelet to create hybrid resource allocation models. This brings flexibility
and efficiency to high-performance workloads without sacrificing NUMA alignment.
Real-world use cases
Here are a few practical scenarios demonstrating how this feature can be applied, depending on the configured Topology Manager scope:
1. Tightly-coupled database (Topology manager's pod scope)
Consider a latency-sensitive database pod that includes a main database container, a local metrics exporter, and a backup agent sidecar.
When configured with the pod Topology Manager scope, the kubelet performs a
single NUMA alignment based on the entire pod's budget. The database container
gets its exclusive CPU and memory slices from that NUMA node. The remaining
resources from the pod's budget form a new pod shared pool. The metrics
exporter and backup agent run in this pod shared pool. They share resources with
each other, but they are strictly isolated from the database's exclusive slices
and the rest of the node.
This allows you to safely co-locate auxiliary containers on the same NUMA node as your primary workload without wasting dedicated cores on them.
apiVersion: v1
kind: Pod
metadata:
name: tightly-coupled-database
spec:
# Pod-level resources establish the overall budget and NUMA alignment size.
resources:
requests:
cpu: "8"
memory: "16Gi"
limits:
cpu: "8"
memory: "16Gi"
initContainers:
- name: metrics-exporter
image: metrics-exporter:v1
restartPolicy: Always
- name: backup-agent
image: backup-agent:v1
restartPolicy: Always
containers:
- name: database
image: database:v1
# This Guaranteed container gets an exclusive 6 CPU slice from the pod's budget.
# The remaining 2 CPUs and 4Gi memory form the pod shared pool for the sidecars.
resources:
requests:
cpu: "6"
memory: "12Gi"
limits:
cpu: "6"
memory: "12Gi"
2. ML workload with infrastructure sidecars (Topology manager's container scope)
Imagine a pod running a GPU-accelerated ML training workload alongside a generic service mesh sidecar.
Under the container Topology Manager scope, the kubelet evaluates each
container individually. You can grant the ML container exclusive, NUMA-aligned
CPUs and Memory for maximum performance. Meanwhile, the service mesh sidecar
doesn't need to be NUMA-aligned; it can run in the general node-wide shared
pool. The collective resource consumption is still safely bounded by the overall
pod limits, but you only allocate NUMA-aligned, exclusive resources to the
specific containers that actually require them.
apiVersion: v1
kind: Pod
metadata:
name: ml-workload
spec:
# Pod-level resources establish the overall budget constraint.
resources:
requests:
cpu: "4"
memory: "8Gi"
limits:
cpu: "4"
memory: "8Gi"
initContainers:
- name: service-mesh-sidecar
image: service-mesh:v1
restartPolicy: Always
containers:
- name: ml-training
image: ml-training:v1
# Under the 'container' scope, this Guaranteed container receives exclusive,
# NUMA-aligned resources, while the sidecar runs in the node's shared pool.
resources:
requests:
cpu: "3"
memory: "6Gi"
limits:
cpu: "3"
memory: "6Gi"
CPU quotas (CFS) and isolation
When running these mixed workloads within a pod, isolation is enforced differently depending on the allocation:
- Exclusive containers: Containers granted exclusive CPU slices have their CPU CFS quota enforcement disabled at the container level, allowing them to run without being throttled by the Linux scheduler.
- Pod shared pool containers: Containers falling into the pod shared pool have CPU CFS quotas enforced at the pod level, ensuring they do not consume more than the leftover pod budget.
How to enable Pod-Level Resource Managers
Using this feature requires Kubernetes v1.36 or newer. To enable it, you must configure the kubelet with the appropriate feature gates and policies:
- Enable the
PodLevelResourcesandPodLevelResourceManagersfeature gates. - Configure the
Topology Manager
with a policy other than
none(i.e.,best-effort,restricted, orsingle-numa-node). - Set the
Topology Manager scope
to either
podorcontainerusing thetopologyManagerScopefield in theKubeletConfiguration. - Configure the
CPU Manager with
the
staticpolicy. - Configure the
Memory Manager with the
Staticpolicy.
Observability
To help cluster administrators monitor and debug these new allocation models, we have introduced several new kubelet metrics when the feature gate is enabled:
resource_manager_allocations_total: Counts the total number of exclusive resource allocations performed by a manager. Thesourcelabel ("pod" or "node") distinguishes between allocations drawn from the node-level pool versus a pre-allocated pod-level pool.resource_manager_allocation_errors_total: Counts errors encountered during exclusive resource allocation, distinguished by the intended allocationsource("pod" or "node").resource_manager_container_assignments: Tracks the cumulative number of containers running with specific assignment types. Theassignment_typelabel ("node_exclusive", "pod_exclusive", "pod_shared") provides visibility into how workloads are distributed.
Current limitations and caveats
While this feature opens up new possibilities, there are a few things to keep in mind during its alpha phase. Be sure to review the Limitations and caveats in the official documentation for full details on compatibility, requirements, and downgrade instructions.
Getting started and providing feedback
For a deep dive into the technical details and configuration of this feature, check out the official concept documentation:
To learn more about the overall pod-level resources feature and how to assign resources to pods, see:
As this feature moves through Alpha, your feedback is invaluable. Please report any issues or share your experiences via the standard Kubernetes communication channels: