{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "2.1.13"
              },
              {
                "introduced": "2.2.0-alpha"
              },
              {
                "fixed": "2.2.2-alpha"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "79ddfb460847999b807cba76d04e73891f29c6ee"
            },
            {
              "fixed": "df3ecad3a040fd6d4fad4287defe113395de6fd7"
            },
            {
              "fixed": "52057cb33d0c20c0a0453fbabe6c0c96854931b9"
            },
            {
              "fixed": "ef38f926e9cd1f082416c6fff13587bc1f431d72"
            }
          ],
          "repo": "https://github.com/libevent/libevent",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-cvq5-vrvr-j338"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-617",
      "CWE-787"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63388.json"
  },
  "details": "Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has a heap out-of-bounds write in bufferevent_sock.c when bufferevent_socket_set_conn_address_ copies a kernel-supplied AF_UNIX peer address into bufferevent_private.conn_address. Release builds compiled with NDEBUG disable the EVUTIL_ASSERT length guard, and the evhttp accept path can pass a 110-byte sockaddr from accept() into the 28-byte field. An unauthenticated local peer able to connect to an AF_UNIX listener can overwrite the adjacent dns_request pointer and heap data, causing memory corruption with confidentiality, integrity, and availability impact. This issue is fixed in versions 2.1.13 and 2.2.2-alpha.",
  "id": "CVE-2026-63388",
  "modified": "2026-08-23T03:42:59.833014221Z",
  "published": "2026-08-20T17:44:18.435Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/libevent/libevent/releases/tag/release-2.1.13-stable"
    },
    {
      "type": "WEB",
      "url": "https://github.com/libevent/libevent/releases/tag/release-2.2.2-alpha"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63388.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/libevent/libevent/security/advisories/GHSA-cvq5-vrvr-j338"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-63388"
    },
    {
      "type": "FIX",
      "url": "https://github.com/libevent/libevent/commit/52057cb33d0c20c0a0453fbabe6c0c96854931b9"
    },
    {
      "type": "FIX",
      "url": "https://github.com/libevent/libevent/commit/ef38f926e9cd1f082416c6fff13587bc1f431d72"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Libevent: Heap out-of-bounds write in bufferevent_socket_set_conn_address_ reachable via AF_UNIX accept"
}