{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "1.8.6"
              },
              {
                "introduced": "1.9.0"
              },
              {
                "fixed": "1.9.5"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "introduced": "338e6fb681369ff0537719095e22ce9dc602dbf0"
            },
            {
              "fixed": "5853918c4c6a7b12f8becf4bd11ff4362ebb9020"
            },
            {
              "fixed": "f7a4071c766ceea3915415e22134cbe3e581c420"
            },
            {
              "fixed": "647dcb432980b84ede4cb5a008bbd1ccb4ead03d"
            },
            {
              "fixed": "c2aa35409ee0e6515df64da49750f13a0a42c47f"
            },
            {
              "fixed": "ef086bc3e4eedf62be38a910381aae24d49871ff"
            }
          ],
          "repo": "https://github.com/libgit2/libgit2",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-h7gc-w2gg-p9xp"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-295",
      "CWE-297"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53583.json"
  },
  "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, verify_server_cert in src/libgit2/streams/openssl.c uses an inverted !!memcmp result in the GEN_IPADD branch when comparing an IP-literal host with a certificate IP SubjectAltName. OpenSSL builds reject matching IP addresses and accept mismatched IP addresses, allowing a network attacker with a CA-trusted certificate containing any IP SubjectAltName to intercept libgit2 connections to IP-literal HTTPS URLs. DNS SubjectAltName validation and non-OpenSSL TLS backends are not affected. This issue is fixed in versions 1.8.6 and 1.9.5.",
  "id": "CVE-2026-53583",
  "modified": "2026-09-11T03:30:42.053590942Z",
  "published": "2026-08-20T18:39:03.676Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/libgit2/libgit2/releases/tag/v1.8.6"
    },
    {
      "type": "WEB",
      "url": "https://github.com/libgit2/libgit2/releases/tag/v1.9.5"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53583.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/libgit2/libgit2/security/advisories/GHSA-h7gc-w2gg-p9xp"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-53583"
    },
    {
      "type": "FIX",
      "url": "https://github.com/libgit2/libgit2/commit/647dcb432980b84ede4cb5a008bbd1ccb4ead03d"
    },
    {
      "type": "FIX",
      "url": "https://github.com/libgit2/libgit2/commit/c2aa35409ee0e6515df64da49750f13a0a42c47f"
    },
    {
      "type": "FIX",
      "url": "https://github.com/libgit2/libgit2/commit/ef086bc3e4eedf62be38a910381aae24d49871ff"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "libgit2: Inverted IP SubjectAltName Comparison in OpenSSL Backend"
}