CVE-2026-31830 json
sigstore-ruby verifier returns success for DSSE bundles with mismatched in-toto subject digest
published 2026-03-10 8 mo ago modified 2026-06-17 4 mo ago also GHSA-mhg6-2q2v-9h2c , EUVD-2026-10932
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 20%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- rubygems sigstore 0.2.3
- sigstore sigstore 0.2.3
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 7 mo ago
Exploit prediction
0.28% chance of exploitation in the next 30 days, higher than 20% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N |
| GitHub | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| rubygems | sigstore | <0.2.3 |
0.2.3 |
Affected products
- sigstore sigstore-ruby
Classification
- Weakness
-
- CWE-252 Unchecked Return Value
References
Sources
- CVE List CVE-2026-31830
- GitHub Advisory GHSA-mhg6-2q2v-9h2c
- NVD CVE-2026-31830
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