{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "2.2.0-alpha"
              },
              {
                "fixed": "2.2.2-alpha"
              },
              {
                "introduced": "0"
              },
              {
                "fixed": "2.1.13"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "df3ecad3a040fd6d4fad4287defe113395de6fd7"
            },
            {
              "fixed": "79ddfb460847999b807cba76d04e73891f29c6ee"
            },
            {
              "fixed": "5cb95ba2f804f8aff46f88d58391c71e1251cd1c"
            },
            {
              "fixed": "9db091b04f569be3a700fa9860ef02f90b830af9"
            }
          ],
          "repo": "https://github.com/libevent/libevent",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-c2pj-cg4r-88c8"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-908"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63381.json"
  },
  "details": "Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has a use-after-free in buffer.c when evbuffer_add_buffer_reference processes an output buffer whose out_total_len is zero. evbuffer_free_all_chains frees the initial empty chain without resetting outbuf-\u003efirst, outbuf-\u003elast, or outbuf-\u003elast_with_datap, and APPEND_CHAIN_MULTICAST subsequently dereferences the dangling chain pointer. A caller that can drive this buffer state can cause memory corruption or a process crash. This issue is fixed in versions 2.1.13 and 2.2.2-alpha.",
  "id": "CVE-2026-63381",
  "modified": "2026-09-11T03:30:36.889082280Z",
  "published": "2026-08-20T17:50:09.322Z",
  "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-2026-63381.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/libevent/libevent/security/advisories/GHSA-c2pj-cg4r-88c8"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-63381"
    },
    {
      "type": "FIX",
      "url": "https://github.com/libevent/libevent/commit/5cb95ba2f804f8aff46f88d58391c71e1251cd1c"
    },
    {
      "type": "FIX",
      "url": "https://github.com/libevent/libevent/commit/9db091b04f569be3a700fa9860ef02f90b830af9"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Libevent: Dangling Pointer in `evbuffer_add_buffer_reference`"
}