CVE-2026-49834 (GCVE-0-2026-49834)
Vulnerability from cvelistv5
Published
2026-07-17 19:20
Modified
2026-07-17 19:42
Severity ?
5.9 (Medium) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
CWE
  • CWE-347 - Improper Verification of Cryptographic Signature
Summary
sigstore-go is a Go library for Sigstore signing and verification. Prior to 1.2.0, a verifier configured with WithTransparencyLog(N>1) or WithSignedCertificateTimestamps(N>1) counts verified witnesses per entry or per validation path rather than per log authority, allowing a single compromised transparency log or CT log to satisfy multi-log threshold requirements and defeat the multi-log policy. This issue is fixed in version 1.2.0.
References
Impacted products
Vendor Product Version
sigstore sigstore-go Version: < 1.2.0
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