{
  "id": "CVE-2026-53583",
  "url": "https://spydr.io/cve/CVE-2026-53583",
  "published": "2026-08-20T19:16:54.500Z",
  "modified": "2026-09-09T21:19:49.197Z",
  "score": 6.5,
  "severity": "medium",
  "cvss_version": "3.1",
  "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
  "score_source": "github.com",
  "epss": 0.00238,
  "epss_percentile": 0.13511,
  "exploited": false,
  "kev": null,
  "ssvc_exploitation": "poc",
  "vendors": [
    "libgit2"
  ],
  "products": [
    "libgit2"
  ],
  "cwes": [
    "CWE-295",
    "CWE-297"
  ],
  "description": "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.",
  "status": "Awaiting Analysis",
  "score_type": "Secondary",
  "scores": {
    "cvss_v40": null,
    "cvss_v31": 6.5,
    "cvss_v30": null
  },
  "references": [
    {
      "url": "https://github.com/libgit2/libgit2/commit/647dcb432980b84ede4cb5a008bbd1ccb4ead03d",
      "tags": []
    },
    {
      "url": "https://github.com/libgit2/libgit2/commit/c2aa35409ee0e6515df64da49750f13a0a42c47f",
      "tags": []
    },
    {
      "url": "https://github.com/libgit2/libgit2/commit/ef086bc3e4eedf62be38a910381aae24d49871ff",
      "tags": []
    },
    {
      "url": "https://github.com/libgit2/libgit2/releases/tag/v1.8.6",
      "tags": []
    },
    {
      "url": "https://github.com/libgit2/libgit2/releases/tag/v1.9.5",
      "tags": []
    },
    {
      "url": "https://github.com/libgit2/libgit2/security/advisories/GHSA-h7gc-w2gg-p9xp",
      "tags": []
    }
  ],
  "nvd_url": "https://nvd.nist.gov/vuln/detail/CVE-2026-53583",
  "covered_in": [],
  "attribution": [
    {
      "source": "NVD",
      "url": "https://nvd.nist.gov",
      "notice": "This product uses data from the NVD API but is not endorsed or certified by the NVD."
    },
    {
      "source": "CISA KEV",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "notice": "Known exploited vulnerabilities from the CISA KEV catalog."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss",
      "notice": "Exploit prediction scores from FIRST EPSS."
    }
  ]
}