https://vulnerability.circl.lu Contains only the most 10 recent entries. http://www.rssboard.org/rss-specification python-feedgen en Thu, 08 Oct 2026 20:11:17 +0000 https://vulnerability.circl.lu/vuln/fkie_cve-2026-31830 <p>sigstore-ruby is a pure Ruby implementation of the sigstore verify command from the sigstore/cosign project. Prior to 0.2.3, Sigstore::Verifier#verify does not propagate the VerificationFailure returned by verify_in_toto when the artifact digest does not match the digest in the in-toto attestation subject. As a result, verification of DSSE bundles containing in-toto statements returns VerificationSuccess regardless of whether the artifact matches the attested subject. This vulnerability is fixed in 0.2.3.</p> <p>sigstore-ruby is a pure Ruby implementation of the sigstore verify command from the sigstore/cosign project. Prior to 0.2.3, Sigstore::Verifier#verify does not propagate the VerificationFailure returned by verify_in_toto when the artifact digest does not match the digest in the in-toto attestation subject. As a result, verification of DSSE bundles containing in-toto statements returns VerificationSuccess regardless of whether the artifact matches the attested subject. This vulnerability is fixed in 0.2.3.</p> https://vulnerability.circl.lu/vuln/fkie_cve-2026-31830 https://vulnerability.circl.lu/vuln/ghsa-mhg6-2q2v-9h2c <p><strong>Affected:</strong> RubyGems: sigstore</p> <p>### Summary</p> <p>`Sigstore::Verifier#verify` does not propagate the `VerificationFailure` returned by `verify_in_toto` when the artifact digest does not match the digest in the in-toto attestation subject. As a result, verification of DSSE bundles containing in-toto statements returns `VerificationSuccess` regardless of whether the artifact matches the attested subject.</p> <p>### Details</p> <p>In `lib/sigstore/verifier.rb`, the verify method calls `verify_in_toto` (line 176) without capturing or checking its return value:</p> <p>`verify_in_toto(input, in_toto)`</p> <p>When `verify_in_toto` detects a digest mismatch, it returns a `VerificationFailure` object. Because the caller discards this return value, execution unconditionally falls through to return `VerificationSuccess`. This is the only verification sub-check in the method (out of 12) whose failure is not propagated.</p> <p>The message_signature code path is not affected.</p> <p>### Impact</p> <p>An attacker who possesses a valid signed DSSE bundle containing an in-toto attestation for artifact A can present it as a valid attestation for a different artifact B. All other verification checks (DSSE envelope signature, certificate chain, Rekor inclusion, SCTs, policy) pass because they are independent of the artifact content. Only the in-toto subject digest check detects the mismatch, and its result is discarded.</p> <p>This allows an attacker to bypass artifact-to-attestation binding for any consumer that relies on `Sigstore::Verifier#verify` to validate DSSE/in-toto bu…</p> <p><strong>Affected:</strong> RubyGems: sigstore</p> <p>### Summary</p> <p>`Sigstore::Verifier#verify` does not propagate the `VerificationFailure` returned by `verify_in_toto` when the artifact digest does not match the digest in the in-toto attestation subject. As a result, verification of DSSE bundles containing in-toto statements returns `VerificationSuccess` regardless of whether the artifact matches the attested subject.</p> <p>### Details</p> <p>In `lib/sigstore/verifier.rb`, the verify method calls `verify_in_toto` (line 176) without capturing or checking its return value:</p> <p>`verify_in_toto(input, in_toto)`</p> <p>When `verify_in_toto` detects a digest mismatch, it returns a `VerificationFailure` object. Because the caller discards this return value, execution unconditionally falls through to return `VerificationSuccess`. This is the only verification sub-check in the method (out of 12) whose failure is not propagated.</p> <p>The message_signature code path is not affected.</p> <p>### Impact</p> <p>An attacker who possesses a valid signed DSSE bundle containing an in-toto attestation for artifact A can present it as a valid attestation for a different artifact B. All other verification checks (DSSE envelope signature, certificate chain, Rekor inclusion, SCTs, policy) pass because they are independent of the artifact content. Only the in-toto subject digest check detects the mismatch, and its result is discarded.</p> <p>This allows an attacker to bypass artifact-to-attestation binding for any consumer that relies on `Sigstore::Verifier#verify` to validate DSSE/in-toto bu…</p> https://vulnerability.circl.lu/vuln/ghsa-mhg6-2q2v-9h2c