{"id":"GHSA-273p-m2cw-6833","summary":"Rekor's COSE v0.0.1 entry type nil pointer dereference in Canonicalize via empty Message","details":"## Summary\n\nRekor’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`.\n\n## Impact\n\nA malformed proposed entry of the `cose/v0.0.1` type can cause a panic on a thread within the Rekor process. The thread is recovered so the client receives a 500 error message and service still continues, so the availability impact of this is minimal.\n\n## Patches\n\nUpgrade to v1.5.0\n\n## Workarounds\n\nNone","aliases":["CVE-2026-23831","GO-2026-4354"],"modified":"2026-09-10T03:50:32.343012154Z","published":"2026-01-22T18:41:23Z","database_specific":{"severity":"MODERATE","github_reviewed":true,"github_reviewed_at":"2026-01-22T18:41:23Z","nvd_published_at":"2026-01-22T22:16:19Z","cwe_ids":["CWE-476"]},"references":[{"type":"WEB","url":"https://github.com/sigstore/rekor/security/advisories/GHSA-273p-m2cw-6833"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-23831"},{"type":"WEB","url":"https://github.com/sigstore/rekor/commit/39bae3d192bce48ef4ef2cbd1788fb5770fee8cd"},{"type":"PACKAGE","url":"https://github.com/sigstore/rekor"},{"type":"WEB","url":"https://github.com/sigstore/rekor/releases/tag/v1.5.0"}],"affected":[{"package":{"name":"github.com/sigstore/rekor","ecosystem":"Go","purl":"pkg:golang/github.com/sigstore/rekor"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.5.0"}]}],"database_specific":{"last_known_affected_version_range":"\u003c= 1.4.3","source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/01/GHSA-273p-m2cw-6833/GHSA-273p-m2cw-6833.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"}]}