CVE-2026-44309 (GCVE-0-2026-44309)
Vulnerability from cvelistv5
Published
2026-05-15 16:22
Modified
2026-05-15 17:43
CWE
  • CWE-347 - Improper Verification of Cryptographic Signature
  • CWE-295 - Improper Certificate Validation
Summary
Gitsign is a keyless Sigstore to signing tool for Git commits with your a GitHub / OIDC identity. Prior to 0.16.0, gitsign verify and gitsign verify-tag re-encode commit/tag objects through go-git's EncodeWithoutSignature before checking the signature, instead of verifying against the raw git object bytes. For malformed objects with duplicate tree headers, git-core and go-git parse different trees: git-core uses the first, go-git uses the second. A signature crafted over the go-git-normalized form (second tree) passes gitsign verify while git-core resolves the commit to a completely different tree. This breaks the invariant that a verified signature, the commit semantics git-core presents to users, and the object hash logged in Rekor all refer to the same content. This vulnerability is fixed in 0.16.0.
Impacted products
Vendor Product Version
sigstore gitsign Version: < 0.16.0
Create a notification for this product.
Show details on NVD website


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