{"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":"2026-08-21T21:46:05.425Z"},"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"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-21T20:58:39.443105Z","id":"CVE-2026-53586","options":[{"Exploitation":"none"},{"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":"2026-08-21T21:46:05.425Z"}}]}}