Summary
kcp is missing update validation allows arbitrary LogicalCluster status patches through initializingworkspaces Virtual Workspace
Details
The issue occurs because the rest.ValidateObjectUpdateFunc is not being called within the DefaultDynamicDelegatedStoreFuncs. As a result, the intended status overwrite protection from initializers never gets called, allowing arbitrary logicalcluster status patches.
Workarounds
- Further limit access to the
initializeverb onWorkspaceTypeobjects (see documentation for details). - Only use trusted
WorkspaceTypeobjects.
References
See the pull request (#3599).
Impact
Because UPDATE validation is not being applied, it is possible for an actor with access to an instance of the initializingworkspaces virtual workspace to run arbitrary patches on the status field of LogicalCluster objects while the workspace is initializing.
This allows to add or remove any initializers as well as changing the phase of a LogicalCluster (to "Ready" for example).
As this effectively allows to skip certain initializers or the entire initialization phase, potential integrations with external systems such as billing or security could be affected. Their initializers could be skipped by a WorkspaceType that adds another initializer and grants permissions to the virtual workspace to a rogue or compromised entity.
Who is impacted?
- Impacts other owners of
WorkspaceTypeswith initializers that are inherited by otherWorkspaceTypes. - Impacts developers using the
virtual/frameworkpackage to create their own virtualworkspaces if they are using UpdateFuncs in their custom storageWrappers.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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The problem has been patched in #3599 and is available in kcp 0.28.3 and higher.
Frequently Asked Questions
- What is GHSA-Q6HV-WCJR-WP8H? GHSA-Q6HV-WCJR-WP8H is a low-severity security vulnerability in github.com/kcp-dev/kcp (go), affecting versions <= 0.28.1. It is fixed in 0.28.3.
- Which versions of github.com/kcp-dev/kcp are affected by GHSA-Q6HV-WCJR-WP8H? github.com/kcp-dev/kcp (go) versions <= 0.28.1 is affected.
- Is there a fix for GHSA-Q6HV-WCJR-WP8H? Yes. GHSA-Q6HV-WCJR-WP8H is fixed in 0.28.3. Upgrade to this version or later.
- Is GHSA-Q6HV-WCJR-WP8H exploitable, and should I be worried? Whether GHSA-Q6HV-WCJR-WP8H is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether GHSA-Q6HV-WCJR-WP8H is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix GHSA-Q6HV-WCJR-WP8H? Upgrade
github.com/kcp-dev/kcpto 0.28.3 or later.