CVE-2025-29922

Workarounds

For users unable to upgrade to one of the patched versions, the following guidance can be given:

• Minimise the set of people with apiexport/content sub-resource access to APIExport resources. Be aware that this has to apply to all workspaces to be effective.
• Filter incoming requests in a reverse proxy with a similar logic as the authorizer added in the referenced pull request.

References

See pull request (https://github.com/kcp-dev/kcp/pull/3338).

The APIExport Virtual Workspace can be used to manage objects in workspaces that bind that APIExport for resources defined in the APIExport or specified and accepted via permission claims. This allows an API provider (via their APIExport) scoped down access to workspaces of API consumers to provide their services properly.

The identified vulnerability allows creating or deleting an object via the APIExport VirtualWorkspace in any arbitrary target workspace for pre-existing resources. By design, this should only be allowed when the workspace owner decides to give access to an API provider by creating an APIBinding.

With this vulnerability, it is possible for an attacker to create and delete objects even if none of these requirements are satisfied, i.e. even if there is no APIBinding in that workspace at all or the workspace owner has created an APIBinding, but rejected a permission claim.

CVE-2025-29922 has a CVSS score of 9.6 (Critical). The vector is network-reachable, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (0.26.3); upgrading removes the vulnerable code path.

Kodem intelligence

A fix for this issue has been identified and has been published with kcp 0.26.3 and 0.27.0.

1. What is CVE-2025-29922? CVE-2025-29922 is a critical-severity security vulnerability in github.com/kcp-dev/kcp (go), affecting versions < 0.26.3. It is fixed in 0.26.3.
2. How severe is CVE-2025-29922? CVE-2025-29922 has a CVSS score of 9.6 (Critical). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of github.com/kcp-dev/kcp are affected by CVE-2025-29922? github.com/kcp-dev/kcp (go) versions < 0.26.3 is affected.
4. Is there a fix for CVE-2025-29922? Yes. CVE-2025-29922 is fixed in 0.26.3. Upgrade to this version or later.
5. Is CVE-2025-29922 exploitable, and should I be worried? Whether CVE-2025-29922 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
6. What actually determines whether CVE-2025-29922 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.
7. How do I fix CVE-2025-29922? Upgrade github.com/kcp-dev/kcp to 0.26.3 or later.