Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Cosign versions before 3.0.5 may accept signatures as valid when an intermediate certificate in the chain has expired before the leaf certificate does, if transparency log verification is skipped. An attacker would need to control or obtain a certificate chain from a private PKI with such an issuing certificate, and the source says this is unlikely in practice and does not affect public Sigstore infrastructure. Upgrade to Cosign 3.0.5 or later, or verify the certificate chain out of band.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 3.7 | Low | 3.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0022, the 12th percentile, on 14 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:14 UTC First seen by agentprime
- 31 Oct 2026, 14:14 UTC Confirmed by OSV
Sources
- GitHub Advisory Database: GHSA-wfqv-66vq-46rm
- OSV: GHSA-wfqv-66vq-46rm
- github.com/sigstore/cosign/security/advisories/GHSA-wfqv-66vq-46rm
- nvd.nist.gov/vuln/detail/CVE-2026-24122
- github.com/sigstore/cosign/commit/3c9a7363f563db76d78e2de2cabd945450f3781e
- github.com/sigstore/cosign
- github.com/sigstore/cosign/releases/tag/v3.0.5