kcp front-proxy does not strip inbound X-Remote-* identity headers, allowing any authenticated client to inject groups/warrants and impersonate system:masters in any workspace
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 0.31.4, 0.32.2
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: total
Summary
kcp is a Kubernetes-like control plane for form-factors and use-cases beyond Kubernetes and container workloads. Prior to 0.31.4 and 0.32.2, the kcp front-proxy does not remove inbound X-Remote-User, X-Remote-Group, or X-Remote-Extra-* identity headers before forwarding requests to shards. Any authenticated tenant can inject X-Remote-Group: system:masters, authorization.kcp.io/warrant, authentication.kcp.io/scopes, or a group used for per-workspace required-group gating, and the shard trusts these values as authenticated identity assertions. This allows cross-workspace impersonation, authorization bypass, and arbitrary reading, writing, or deletion of resources, secrets, RBAC data, APIExports, APIBindings, and LogicalClusters. This issue is fixed in versions 0.31.4 and 0.32.2.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- kcp-dev kcp
fixed in 0.31.4; From 0.32.0 · fixed in 0.32.2
- github.com/kcp-dev/kcpGo
fixed in 0.31.4; From 0.32.0 · fixed in 0.32.2
- github.com/kcp-dev/kcpGo
fixed in 0.31.4
- github.com/kcp-dev/kcpGo
From 0.32.0 · fixed in 0.32.2