CVE-2026-44309
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.
- CVSS 3.1
- 5.3
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N - EPSS
- 0.1% chance of exploitation in the next 30 days; higher than 1% of CVEs (scores of 2026-10-25)
- CWEs
- CWE-295, CWE-347
- Published
- Modified
- Record from
- the NVD, synced
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-7rmh-48mx-2vwc | Go | github.com/sigstore/gitsign | <0.16.0 | 0.16.0 |
| GO-2026-5233 | Go | github.com/sigstore/gitsign | <0.16.0 | 0.16.0 |