CVE-2026-44309

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{"affected": [{"affectedData": [{"product": "gitsign", "vendor": "sigstore", "versions": [{"status": "affected", "version": "< 0.16.0"}]}], "source": "security-advisories@github.com"}], "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."}, {"lang": "es", "value": "Gitsign es una herramienta de firma Sigstore sin clave para commits de Git con tu identidad de GitHub / OIDC. Antes de la versi\u00f3n 0.16.0, gitsign verify y gitsign verify-tag recodificaban objetos de commit/etiqueta a trav\u00e9s de EncodeWithoutSignature de go-git antes de verificar la firma, en lugar de verificar contra los bytes brutos del objeto git. Para objetos malformados con encabezados de \u00e1rbol duplicados, git-core y go-git analizan \u00e1rboles diferentes: git-core usa el primero, go-git usa el segundo. Una firma creada sobre la forma normalizada por go-git (segundo \u00e1rbol) pasa gitsign verify mientras que git-core resuelve el commit a un \u00e1rbol completamente diferente. Esto rompe el invariante de que una firma verificada, la sem\u00e1ntica del commit que git-core presenta a los usuarios y el hash del objeto registrado en Rekor se refieren todos al mismo contenido. Esta vulnerabilidad est\u00e1 corregida en la versi\u00f3n 0.16.0."}], "id": "CVE-2026-44309", "lastModified": "2026-10-26T14:10:00.130", "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"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-44309", "options": [{"exploitation": "poc"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-05-15T17:43:27.049597Z", "version": "2.0.3"}}]}, "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"}, {"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "url": "https://github.com/sigstore/gitsign/security/advisories/GHSA-7rmh-48mx-2vwc"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-295"}, {"lang": "en", "value": "CWE-347"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{}

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