CVE-2026-23831: Rekor's COSE v0.0.1 entry type nil pointer dereference in Canonicalize via empty Message

January 22, 2026 (updated January 23, 2026)

Rekor’s cose v0.0.1 entry implementation can panic on attacker-controlled input when canonicalizing a proposed entry with an empty spec.message. validate() returns nil (success) when message is empty, leaving sign1Msg uninitialized, and Canonicalize() later dereferences v.sign1Msg.Payload.

References

github.com/advisories/GHSA-273p-m2cw-6833
github.com/sigstore/rekor
github.com/sigstore/rekor/commit/39bae3d192bce48ef4ef2cbd1788fb5770fee8cd
github.com/sigstore/rekor/releases/tag/v1.5.0
github.com/sigstore/rekor/security/advisories/GHSA-273p-m2cw-6833
nvd.nist.gov/vuln/detail/CVE-2026-23831

Code Behaviors & Features

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