Kyverno: ServiceAccount token leaked to external servers via apiCall service URL
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.1epss 0.6%
exploitation probability
0.6%top 55% of all CVEs
observed exploitation
nono source reports it
Kyverno is a policy engine designed for cloud native platform engineering teams. Prior to versions 1.18.0-rc1, 1.17.2-rc1, and 1.16.4, Kyverno's apiCall feature in ClusterPolicy automatically attaches the admission controller's ServiceAccount token to outgoing HTTP requests. The service URL has no validation — it can point anywhere, including attacker-controlled servers. Since the admission controller SA has permissions to patch webhook configurations, a stolen token leads to full cluster compromise. Versions 1.18.0-rc1, 1.17.2-rc1, and 1.16.4 patch the issue.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Affected products
kyverno · kyvernoReferences
https://github.com/kyverno/kyverno/commit/bc4f91c4801b1eaa2edc0a14e2f1b0af8cf0c1f5https://github.com/kyverno/kyverno/commit/c2eab00033e635bda4e4efb58c1b472b41728bb6https://github.com/kyverno/kyverno/commit/f70e8ac1e7acd2e3844f9553e4a884f07f953de0https://github.com/kyverno/kyverno/security/advisories/GHSA-f9g8-6ppc-pqq4