GHSA-c7xh-gjv4-4jgv
kcp's impersonation allows access to global administrative groups
GHSA-c7xh-gjv4-4jgv is a medium vulnerability (CVSS 6.4) in github.com/kcp-dev/kcp, published December 11, 2024. No source lists public exploit code. Fixed in github.com/kcp-dev/kcp 0.26.1.
- Severity
- 6.4 MediumCVSS 3.1, GitHub Advisories
- Exploit chance
- UnscoredNo EPSS score yet
- Exploitation
- None knownNot on CISA’s or ENISA’s lists
- Fixed in
0.26.1github.com/kcp-dev/kcp +1 more
Description
Impact
Impersonation is a feature of the Kubernetes API, allowing to override user information. As downstream project, kcp inherits this feature. As per the linked documentation a specific level of privilege (usually assigned to cluster admins) is required for impersonation.
The vulnerability in kcp affects kcp installations in which users are granted the cluster-admin ClusterRole (or comparably high permission levels that grant impersonation access; the verb in question is impersonate) within their respective workspaces. As kcp builds around self-service confined within workspaces, most installations would likely grant such workspace access to their users. Such users can impersonate special global administrative groups, which circumvent parts of the authorizer chains, e.g. maximal permission policies.
Patches
The problem has been patched in #3206 and is available in kcp 0.26.1 and higher.
Workarounds
- Not assigning the
cluster-adminrole (or any other role granting blanket impersonation permissions) to users. - A reverse proxy between users and kcp to check for the
Impersonate-Groupheader and reject requests that impersonate global administrative groups.
References
See the pull request (#3206).
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Affected packages
| Package | Affected | Fixed |
|---|---|---|
github.com/kcp-dev/kcpGo | through 0.26.0 | 0.26.1 |
github.com/kcp-dev/kcpGo | before 0.26.1 | 0.26.1 |
What each source reports
GitHub Advisories Score used
kcp's impersonation allows access to global administrative groups
Impact
Impersonation is a feature of the Kubernetes API, allowing to override user information. As downstream project, kcp inherits this feature. As per the linked documentation a specific level of privilege (usually assigned to cluster admins) is required for impersonation.
The vulnerability in kcp affects kcp installations in which users are granted the cluster-admin ClusterRole (or comparably high permission levels that grant impersonation access; the verb in question is impersonate) within their respective workspaces. As kcp builds around self-service confined within workspaces, most installations would likely grant such workspace access to their users. Such users can impersonate special global administrative groups, which circumvent parts of the authorizer chains, e.g. maximal permission policies.
Patches
The problem has been patched in #3206 and is available in kcp 0.26.1 and higher.
Workarounds
- Not assigning the
cluster-adminrole (or any other role granting blanket impersonation permissions) to users. - A reverse proxy between users and kcp to check for the
Impersonate-Groupheader and reject requests that impersonate global administrative groups.
References
See the pull request (#3206).
- Record
GHSA-c7xh-gjv4-4jgv- CVSS 3.1
- 6.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N - Weakness
- CWE-285
- Updated
- 2026-11-02
OSV
kcp's impersonation allows access to global administrative groups
Impact
Impersonation is a feature of the Kubernetes API, allowing to override user information. As downstream project, kcp inherits this feature. As per the linked documentation a specific level of privilege (usually assigned to cluster admins) is required for impersonation.
The vulnerability in kcp affects kcp installations in which users are granted the cluster-admin ClusterRole (or comparably high permission levels that grant impersonation access; the verb in question is impersonate) within their respective workspaces. As kcp builds around self-service confined within workspaces, most installations would likely grant such workspace access to their users. Such users can impersonate special global administrative groups, which circumvent parts of the authorizer chains, e.g. maximal permission policies.
Patches
The problem has been patched in #3206 and is available in kcp 0.26.1 and higher.
Workarounds
- Not assigning the
cluster-adminrole (or any other role granting blanket impersonation permissions) to users. - A reverse proxy between users and kcp to check for the
Impersonate-Groupheader and reject requests that impersonate global administrative groups.
References
See the pull request (#3206).
- Record
GHSA-c7xh-gjv4-4jgv- CVSS 3.1
- 6.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N - Weakness
- CWE-285
- Updated
- 2026-11-02
OSVGO-2024-3325No score
kcp's impersonation allows access to global administrative groups in github.com/kcp-dev/kcp
kcp's impersonation allows access to global administrative groups in github.com/kcp-dev/kcp
- Record
GO-2024-3325- Updated
- 2026-11-02
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | GitHub Advisories, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.