{"id":"UBUNTU-CVE-2026-54787","details":"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.","modified":"2026-08-06T00:20:54Z","published":"2026-07-31T23:17:00Z","upstream":["CVE-2026-54787"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-54787"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-54787"},{"type":"REPORT","url":"https://github.com/sigstore/sigstore-go/security/advisories/GHSA-wqqc-jjcq-vfxm"},{"type":"REPORT","url":"https://github.com/sigstore/sigstore-go/pull/642"},{"type":"REPORT","url":"https://github.com/sigstore/sigstore-go/commit/4594ab4c779d08be1f4419803a8249188f35ed5f"},{"type":"REPORT","url":"https://github.com/sigstore/sigstore-go/commit/4594ab4c779d08be1f4419803a8249188f35ed5f"},{"type":"REPORT","url":"https://github.com/sigstore/sigstore-go/releases/tag/v1.2.1"}],"affected":[{"package":{"name":"sigstore-go","ecosystem":"Ubuntu:Pro:26.04:LTS","purl":"pkg:deb/ubuntu/sigstore-go?arch=source&distro=esm-apps%2Fresolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.7.1-2","0.7.3-1","0.7.3-2","1.1.4-1","1.1.4-1ubuntu0.26.04.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"golang-github-sigstore-sigstore-go-dev","binary_version":"1.1.4-1ubuntu0.26.04.1~esm1"},{"binary_name":"sigstore-go","binary_version":"1.1.4-1ubuntu0.26.04.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-54787.json"}}],"schema_version":"1.8.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N"},{"type":"Ubuntu","score":"medium"}]}