Auth bypass in Kcp
CVE-2026-39429
kcp is a Kubernetes-like control plane for form-factors and use-cases beyond Kubernetes and container workloads. Prior to 0.30.3 and 0.29.3, the cache server is directly exposed by the root shard and has no authentication or authorization…
EPSS: 0.004 (35.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N.
Affected products
- Kcp
- Kcp-dev Kcp — versions >= 0.30.0, < 0.30.3, < 0.29.3
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Mitigation, Vendor Advisory)
- security-advisories@github.com (x_refsource_MISC, Release Notes)
- security-advisories@github.com (x_refsource_MISC, Release Notes)
Frequently asked questions
- What is CVE-2026-39429?
- CVE-2026-39429 is a high-severity vulnerability in Kcp, classified under Authentication Bypass by Assumed-Immutable Data. CVSS score: 8.2/10. Published 2026-04-08.
- How severe is CVE-2026-39429?
- High severity. CVSS v3 base score is 8.2 out of 10.