CVE-2026-31830Network attack vector

Artifact verification bypass via discarded digest failure

Published Mar 10, 2026 · Updated Mar 10, 2026

Artifact-verification bypass in Sigstore sigstore-ruby before 0.2.3 allows remote attackers to accept a mismatched DSSE attestation. Sigstore::Verifier#verify discards the VerificationFailure returned by verify_in_toto after an in-toto subject digest mismatch, then falls through to VerificationSuccess. Exploitation requires a valid signed DSSE bundle for one artifact and a consumer that relies on this method, allowing that attestation to be presented for a different artifact.

CVSS severity7.5
High
EPSS probability0.22%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Artifact-verification bypass in Sigstore sigstore-ruby before 0.2.3 allows remote attackers to accept a mismatched DSSE attestation. Sigstore::Verifier#verify discards the VerificationFailure returned by verify_in_toto after an in-toto subject digest mismatch, then falls through to VerificationSuccess. Exploitation requires a valid signed DSSE bundle for one artifact and a consumer that relies on this method, allowing that attestation to be presented for a different artifact.

The record

CVE
CVE-2026-31830
Published
Mar 10, 2026
Updated
Mar 10, 2026
Vendor
Sigstore
Product
sigstore-ruby
Classifications
CWE-252, T1553
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 10, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 10, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 0.2.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Sigstore · sigstore-rubyversion=< 0.2.3

Published CVSS scores

7.5GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-252Unchecked Return Value
T1553Subvert Trust Controls

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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