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SigstoreApplication

CVE-2026-31830

HIGH · 7.5 CVSS v3.1 Published 2026-03-10
Fix available
A fix is available. Upgrade to 0.2.3 or later.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

In sigstore-ruby versions prior to 0.2.3, the Sigstore::Verifier#verify method fails to propagate VerificationFailure when the artifact digest does not match the digest in the in-toto attestation subject. This causes verification of DSSE bundles containing in-toto statements to incorrectly return VerificationSuccess even when the artifact does not match the attested subject, resulting in false positive verifications.

MitigationUpgrade sigstore-ruby to version 0.2.3 or later to ensure proper verification failure propagation when artifact digests do not match attestation subjects.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
SigstoreApplication
Affected:< 0.2.3

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify sigstore-ruby installation
    Run 'gem list sigstore' or check your Gemfile/Gemfile.lock for the sigstore gem
    Affected if The gem is present in the project dependencies
  2. Determine installed version
    Run 'gem list sigstore' or check the version specified in your Gemfile.lock
    Affected if Version is less than 0.2.3 (e.g., 0.2.2, 0.2.1, 0.2.0, or any version prior)
  3. Check for DSSE bundle verification usage
    Inspect code that calls Sigstore::Verifier#verify with DSSE bundles containing in-toto statements
    Affected if The application uses Sigstore::Verifier to verify DSSE bundles with in-toto attestations where the artifact digest may differ from the attestation subject digest

You are affected if sigstore-ruby version is below 0.2.3 and your code uses the Verifier to process DSSE bundles with in-toto statements where digest verification failure would be silently ignored.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 0.2.3 or later
Fixed in 0.2.3
Interim mitigation

Upgrade sigstore-ruby to version 0.2.3 or later to ensure proper verification failure propagation when artifact digests do not match attestation subjects.

Recommended fix High confidence

0.2.3 or later

  1. Check the current version of sigstore-ruby gem in your project (e.g., run `gem list sigstore-ruby` or check your Gemfile)
  2. Update the sigstore-ruby gem to version 0.2.3 or later by running `gem install sigstore-ruby -v '~> 0.2.3'` or updating your Gemfile with `gem 'sigstore-ruby', '~> 0.2.3'` and running `bundle update sigstore-ruby`
  3. Verify the upgrade was successful by checking the installed version
  4. Test your verification workflows to confirm the fix is working correctly

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Sigstore Scoped from the published advisory
  • Consultation2.0 h
  • Implementation1.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,060
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,696.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-31830 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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