{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-44309", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-05-05T19:00:06.021Z", "datePublished": "2026-05-15T16:22:51.260Z", "dateUpdated": "2026-05-15T17:43:59.446Z"}, "containers": {"cna": {"title": "gitsign verify accepts signatures over go-git-normalized bytes, enabling trust confusion on malformed commits", "problemTypes": [{"descriptions": [{"cweId": "CWE-347", "lang": "en", "description": "CWE-347: Improper Verification of Cryptographic Signature", "type": "CWE"}]}, {"descriptions": [{"cweId": "CWE-295", "lang": "en", "description": "CWE-295: Improper Certificate Validation", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N", "version": "3.1"}}], "references": [{"name": "https://github.com/sigstore/gitsign/security/advisories/GHSA-7rmh-48mx-2vwc", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/sigstore/gitsign/security/advisories/GHSA-7rmh-48mx-2vwc"}], "affected": [{"vendor": "sigstore", "product": "gitsign", "versions": [{"version": "< 0.16.0", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-05-15T16:22:51.260Z"}, "descriptions": [{"lang": "en", "value": "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."}], "source": {"advisory": "GHSA-7rmh-48mx-2vwc", "discovery": "UNKNOWN"}}, "adp": [{"references": [{"url": "https://github.com/sigstore/gitsign/security/advisories/GHSA-7rmh-48mx-2vwc", "tags": ["exploit"]}], "metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-05-15T17:43:27.049597Z", "id": "CVE-2026-44309", "options": [{"Exploitation": "poc"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-05-15T17:43:59.446Z"}}]}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "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."}], "id": "CVE-2026-44309", "lastModified": "2026-05-15T17:16:47.297", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N", "version": "3.1"}, "exploitabilityScore": 1.6, "impactScore": 3.6, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-05-15T17:16:47.297", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/sigstore/gitsign/security/advisories/GHSA-7rmh-48mx-2vwc"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-295"}, {"lang": "en", "value": "CWE-347"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,0.16.0)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "gitsign", "source": "cna", "vendor": "sigstore"}, "product": "gitsign", "vendor": "sigstore"}], "created": "2026-05-15T17:30:04.314049+00:00", "updated": "2026-05-15T17:30:04.548653+00:00", "vendors": ["sigstore", "sigstore$PRODUCT$gitsign"]}