CVE-2026-39984: Improper Certificate Validation

Sigstore Timestamp Authority is a service for issuing RFC 3161 timestamps. Versions 2.0.5 and below contain an authorization bypass vulnerability in the VerifyTimestampResponse function. VerifyTimestampResponse correctly verifies the certificate chain signature, but the TSA-specific constraint...

Sigstore Timestamp Authority has Improper Certificate Validation in verifier

Authorization bypass via certificate bag manipulation in sigstore/timestamp-authority verifier An authorization bypass vulnerability exists in sigstore/timestamp-authority verifier timestamp-authority/v2/pkg/verification: VerifyTimestampResponse function correctly verifies the certificate chain b...