{"id":"CVE-2026-23831","aliases":["GHSA-273p-m2cw-6833","GO-2026-4354"],"url":"https://o3.security/vulnerability/CVE-2026-23831","summary":"Rekor COSE v0.0.1 Canonicalize crashes when passed empty Message","details":"Rekor is a software supply chain transparency log. In versions 1.4.3 and below, the entry implementation can panic on attacker-controlled input when canonicalizing a proposed entry with an empty spec.message, causing nil Pointer Dereference. Function validate() returns nil (success) when message is empty, leaving sign1Msg uninitialized, and Canonicalize() later dereferences v.sign1Msg.Payload. A 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. This issue has been fixed in version 1.5.0.","published":"2026-01-22T21:26:22.183Z","modified":"2026-07-31T18:30:10.561576762Z","cvss":{"score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/sigstore/rekor","fixedVersion":"1.5.0"}],"fix":{"url":"https://github.com/sigstore/rekor/commit/39bae3d192bce48ef4ef2cbd1788fb5770fee8cd","label":"sigstore/rekor@39bae3d"},"references":[{"type":"WEB","url":"https://github.com/sigstore/rekor/releases/tag/v1.5.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23831.json"},{"type":"ADVISORY","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":"FIX","url":"https://github.com/sigstore/rekor/commit/39bae3d192bce48ef4ef2cbd1788fb5770fee8cd"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-07-31T18:30:10.561576762Z"}}