CVE-2026-44310Public exploitNetwork attack vector

Signature-verification bypass via swallowed empty-certificate panic

Published May 15, 2026 · Updated May 15, 2026

Signature verification bypass in Sigstore Gitsign 0.4.0 through 0.14.0 allows remote attackers to pass malformed commits via exit status. CertVerifier.Verify indexes the first certificate without checking that GetCertificates returned one, and Streams.Wrap recovers the resulting panic as a nil error. Exploitation requires a certificate-free CMS/PKCS7 signature and a user or CI job that invokes verification and trusts only the process exit code; Git's GOODSIG check blocks that path.

CVSS severity5.4
Medium
EPSS probability0.11%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Signature verification bypass in Sigstore Gitsign 0.4.0 through 0.14.0 allows remote attackers to pass malformed commits via exit status. CertVerifier.Verify indexes the first certificate without checking that GetCertificates returned one, and Streams.Wrap recovers the resulting panic as a nil error. Exploitation requires a certificate-free CMS/PKCS7 signature and a user or CI job that invokes verification and trusts only the process exit code; Git's GOODSIG check blocks that path.

The record

CVE
CVE-2026-44310
Published
May 15, 2026
Updated
May 15, 2026
Vendor
Sigstore
Product
Gitsign
Classifications
CWE-129, CWE-390, T1553.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 15, 2026CVE publishedPublication date reported by the CVE source.
  2. May 15, 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=>= 0.4.0, < 0.15.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Sigstore · Gitsignversion=>= 0.4.0, < 0.15.0

Published CVSS scores

5.4GitHubCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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 exploitPublished

Weakness, pattern, technique

CWE-129Improper Validation of Array Index
CWE-390Detection of Error Condition Without Action
T1553.002Subvert Trust Controls: Code Signing

Public exploit references

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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