{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-53586", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-06-09T19:11:53.484Z", "datePublished": "2026-08-20T18:40:08.673Z", "dateUpdated": "2026-08-20T18:40:08.673Z"}, "containers": {"cna": {"title": "libgit2: HTTP transport can leak credentials to an offsite redirect target", "problemTypes": [{"descriptions": [{"cweId": "CWE-200", "lang": "en", "description": "CWE-200: Exposure of Sensitive Information to an Unauthorized Actor", "type": "CWE"}]}, {"descriptions": [{"cweId": "CWE-522", "lang": "en", "description": "CWE-522: Insufficiently Protected Credentials", "type": "CWE"}]}, {"descriptions": [{"cweId": "CWE-601", "lang": "en", "description": "CWE-601: URL Redirection to Untrusted Site ('Open Redirect')", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"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"}}], "references": [{"name": "https://github.com/libgit2/libgit2/security/advisories/GHSA-2889-x8f6-mc4x", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/libgit2/libgit2/security/advisories/GHSA-2889-x8f6-mc4x"}, {"name": "https://github.com/libgit2/libgit2/commit/07de6a7e438f95ac9a6efd3222a82117e871ed27", "tags": ["x_refsource_MISC"], "url": "https://github.com/libgit2/libgit2/commit/07de6a7e438f95ac9a6efd3222a82117e871ed27"}, {"name": "https://github.com/libgit2/libgit2/commit/af2b29ad0a74d5bac9751376879ddaf848136d3b", "tags": ["x_refsource_MISC"], "url": "https://github.com/libgit2/libgit2/commit/af2b29ad0a74d5bac9751376879ddaf848136d3b"}, {"name": "https://github.com/libgit2/libgit2/commit/c1507abc44647b3acd832a33a5b1c8c9f5ba8821", "tags": ["x_refsource_MISC"], "url": "https://github.com/libgit2/libgit2/commit/c1507abc44647b3acd832a33a5b1c8c9f5ba8821"}, {"name": "https://github.com/libgit2/libgit2/releases/tag/v1.8.6", "tags": ["x_refsource_MISC"], "url": "https://github.com/libgit2/libgit2/releases/tag/v1.8.6"}, {"name": "https://github.com/libgit2/libgit2/releases/tag/v1.9.5", "tags": ["x_refsource_MISC"], "url": "https://github.com/libgit2/libgit2/releases/tag/v1.9.5"}], "affected": [{"vendor": "libgit2", "product": "libgit2", "versions": [{"version": "< 1.8.6", "status": "affected"}, {"version": ">= 1.9.0, < 1.9.5", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-08-20T18:40:08.673Z"}, "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."}], "source": {"advisory": "GHSA-2889-x8f6-mc4x", "discovery": "UNKNOWN"}}}}

{}

{"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."}], "id": "CVE-2026-53586", "lastModified": "2026-08-20T19:16:54.983", "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"}]}, "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": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-200"}, {"lang": "en", "value": "CWE-522"}, {"lang": "en", "value": "CWE-601"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{}