{"id":"CVE-2026-54787","state":"PUBLISHED","title":"sigstore-go fails to check signature timestamps against a signing key's validity period","description":"sigstore-go is a Go library for Sigstore signing and verification. Prior to 1.2.1, sigstore-go does not check a bundle signing timestamp against the validity window of an ExpiringKey wrapping a self-managed long-lived signing key without a certificate, which can allow an attacker holding expired key material to sign accepted bundles. This issue is fixed in version 1.2.1.","publishedAt":"2026-07-31T21:58:14.156Z","updatedAt":"2026-07-31T23:36:13.441Z","severity":{"score":3.1,"label":"Low","version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["sigstore sigstore-go"],"affected":[{"vendor":"sigstore","product":"sigstore-go","versions":[{"version":"< 1.2.1","status":"affected"}]}],"references":["https://github.com/sigstore/sigstore-go/security/advisories/GHSA-wqqc-jjcq-vfxm","https://github.com/sigstore/sigstore-go/pull/642","https://github.com/sigstore/sigstore-go/commit/4594ab4c779d08be1f4419803a8249188f35ed5f","https://github.com/sigstore/sigstore-go/releases/tag/v1.2.1"],"weaknesses":["CWE-324"],"ingestedAt":"2026-10-29T20:12:24.861Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/54xxx/CVE-2026-54787.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-54787","state":"PUBLISHED","datePublished":"2026-07-31T21:58:14.156Z","dateUpdated":"2026-07-31T23:36:13.441Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-06-15T23:23:57.714Z"},"containers":{"cna":{"title":"sigstore-go fails to check signature timestamps against a signing key's validity period","descriptions":[{"lang":"en","value":"sigstore-go is a Go library for Sigstore signing and verification. Prior to 1.2.1, sigstore-go does not check a bundle signing timestamp against the validity window of an ExpiringKey wrapping a self-managed long-lived signing key without a certificate, which can allow an attacker holding expired key material to sign accepted bundles. This issue is fixed in version 1.2.1."}],"affected":[{"vendor":"sigstore","product":"sigstore-go","versions":[{"version":"< 1.2.1","status":"affected"}]}],"references":[{"url":"https://github.com/sigstore/sigstore-go/security/advisories/GHSA-wqqc-jjcq-vfxm","name":"https://github.com/sigstore/sigstore-go/security/advisories/GHSA-wqqc-jjcq-vfxm","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/sigstore/sigstore-go/pull/642","name":"https://github.com/sigstore/sigstore-go/pull/642","tags":["x_refsource_MISC"]},{"url":"https://github.com/sigstore/sigstore-go/commit/4594ab4c779d08be1f4419803a8249188f35ed5f","name":"https://github.com/sigstore/sigstore-go/commit/4594ab4c779d08be1f4419803a8249188f35ed5f","tags":["x_refsource_MISC"]},{"url":"https://github.com/sigstore/sigstore-go/releases/tag/v1.2.1","name":"https://github.com/sigstore/sigstore-go/releases/tag/v1.2.1","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":3.1,"baseSeverity":"LOW","confidentialityImpact":"NONE","integrityImpact":"LOW","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-324","lang":"en","description":"CWE-324: Use of a Key Past its Expiration Date","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-07-31T21:58:14.156Z"},"source":{"advisory":"GHSA-wqqc-jjcq-vfxm","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/sigstore/sigstore-go/security/advisories/GHSA-wqqc-jjcq-vfxm","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-31T23:35:40.966529Z","id":"CVE-2026-54787","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-07-31T23:36:13.441Z"}}]}}}