CVE-2026-53586

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{"affected": [{"affectedData": [{"product": "libgit2", "vendor": "libgit2", "versions": [{"status": "affected", "version": "< 1.8.6"}, {"status": "affected", "version": ">= 1.9.0, < 1.9.5"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "libgit2 is a portable C implementation of the Git core methods provided as a linkable library with a solid API, allowing to build Git functionality into your application. Prior to 1.8.6 and 1.9.5, the built-in HTTP transport in src/libgit2/transports/http.c follows an offsite initial redirect, and handle_remote_auth and handle_auth pass transport->owner->url instead of transport->server.url to the credential callback when the redirected host returns 401 Unauthorized. A callback that scopes credentials to the original trusted URL can therefore return GIT_CREDENTIAL_USERPASS_PLAINTEXT credentials that libgit2 stores in transport->server.cred and sends as an Authorization header to the redirected host. An attacker who controls a trusted Git host or an open redirect on that host can disclose HTTP Basic credentials, personal access tokens, or equivalent credentials. This issue is fixed in versions 1.8.6 and 1.9.5."}, {"lang": "es", "value": "libgit2 es una implementaci\u00f3n port\u00e1til en C de los m\u00e9todos centrales de Git proporcionada como una biblioteca enlazable con una API s\u00f3lida, lo que permite integrar la funcionalidad de Git en su aplicaci\u00f3n. Antes de las versiones 1.8.6 y 1.9.5, el transporte HTTP integrado en src/libgit2/transports/http.c sigue una redirecci\u00f3n inicial externa, y handle_remote_auth y handle_auth pasan transport -> owner -> url en lugar de transport -> server.url a la funci\u00f3n de devoluci\u00f3n de llamada de credenciales cuando el host redirigido devuelve 401 Unauthorized. Una funci\u00f3n de devoluci\u00f3n de llamada que limita el alcance de las credenciales a la URL original de confianza puede, por lo tanto, devolver credenciales GIT_CREDENTIAL_USERPASS_PLAINTEXT que libgit2 almacena en transport -> server.cred y env\u00eda como una cabecera de autorizaci\u00f3n al host redirigido. Un atacante que controla un host Git de confianza o una redirecci\u00f3n abierta en ese host puede divulgar credenciales HTTP Basic, tokens de acceso personal, o credenciales equivalentes. Este problema se corrige en las versiones 1.8.6 y 1.9.5."}], "id": "CVE-2026-53586", "lastModified": "2026-10-26T10:10:00.140", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 6.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 3.6, "source": "security-advisories@github.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-53586", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-08-21T20:58:39.443105Z", "version": "2.0.3"}}]}, "published": "2026-08-20T19:16:54.983", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/libgit2/libgit2/commit/07de6a7e438f95ac9a6efd3222a82117e871ed27"}, {"source": "security-advisories@github.com", "url": "https://github.com/libgit2/libgit2/commit/af2b29ad0a74d5bac9751376879ddaf848136d3b"}, {"source": "security-advisories@github.com", "url": "https://github.com/libgit2/libgit2/commit/c1507abc44647b3acd832a33a5b1c8c9f5ba8821"}, {"source": "security-advisories@github.com", "url": "https://github.com/libgit2/libgit2/releases/tag/v1.8.6"}, {"source": "security-advisories@github.com", "url": "https://github.com/libgit2/libgit2/releases/tag/v1.9.5"}, {"source": "security-advisories@github.com", "url": "https://github.com/libgit2/libgit2/security/advisories/GHSA-2889-x8f6-mc4x"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Awaiting Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-200"}, {"lang": "en", "value": "CWE-522"}, {"lang": "en", "value": "CWE-601"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{"bugzilla": {"description": "libgit2: libgit2: Information disclosure via HTTP redirect allows credential leakage", "id": "2520691", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2520691"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N", "status": "draft"}, "cwe": "CWE-201", "details": ["libgit2 is a portable C implementation of the Git core methods provided as a linkable library with a solid API, allowing to build Git functionality into your application. Prior to 1.8.6 and 1.9.5, the built-in HTTP transport in src/libgit2/transports/http.c follows an offsite initial redirect, and handle_remote_auth and handle_auth pass transport->owner->url instead of transport->server.url to the credential callback when the redirected host returns 401 Unauthorized. A callback that scopes credentials to the original trusted URL can therefore return GIT_CREDENTIAL_USERPASS_PLAINTEXT credentials that libgit2 stores in transport->server.cred and sends as an Authorization header to the redirected host. An attacker who controls a trusted Git host or an open redirect on that host can disclose HTTP Basic credentials, personal access tokens, or equivalent credentials. This issue is fixed in versions 1.8.6 and 1.9.5.", "A flaw was found in libgit2. The built-in HTTP transport component incorrectly handles offsite redirects, leading to the disclosure of sensitive information. An attacker controlling a trusted Git host or an open redirect on that host could exploit this by causing the library to send HTTP Basic credentials or personal access tokens to an unintended third-party server. This vulnerability results in the leakage of user authentication credentials."], "mitigation": {"lang": "en:us", "value": "Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability."}, "name": "CVE-2026-53586", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "rust", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "libgit2", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "rust", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:enterprise_linux_ai:3", "fix_state": "Fix deferred", "package_name": "libgit2", "product_name": "Red Hat Enterprise Linux AI (RHEL AI) 3"}, {"cpe": "cpe:/a:redhat:enterprise_linux_ai:3", "fix_state": "Fix deferred", "package_name": "rust", "product_name": "Red Hat Enterprise Linux AI (RHEL AI) 3"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "libgit2", "product_name": "Red Hat Hardened Images"}], "public_date": "2026-08-20T18:40:08Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-53586\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-53586\nhttps://github.com/libgit2/libgit2/commit/07de6a7e438f95ac9a6efd3222a82117e871ed27\nhttps://github.com/libgit2/libgit2/commit/af2b29ad0a74d5bac9751376879ddaf848136d3b\nhttps://github.com/libgit2/libgit2/commit/c1507abc44647b3acd832a33a5b1c8c9f5ba8821\nhttps://github.com/libgit2/libgit2/releases/tag/v1.8.6\nhttps://github.com/libgit2/libgit2/releases/tag/v1.9.5\nhttps://github.com/libgit2/libgit2/security/advisories/GHSA-2889-x8f6-mc4x"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,1.8.6)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[1.9.0,1.9.5)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "libgit2", "source": "cna", "vendor": "libgit2"}, "product": "libgit2", "vendor": "libgit2"}], "created": "2026-08-20T21:30:05.621617+00:00", "updated": "2026-08-24T14:00:14.513707+00:00", "vendors": ["libgit2", "libgit2$PRODUCT$libgit2"]}