{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "3.4.0"
              },
              {
                "fixed": "3.6.6"
              },
              {
                "introduced": "4.0.0-beta"
              },
              {
                "fixed": "4.0.0-rc1"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "f3e0d5333913bcaace4c8f8711871550accca63f"
            },
            {
              "introduced": "985272ff3d7ebc5e9f24ad9f8fcf8b1d2549f1b6"
            },
            {
              "fixed": "26c0c4e3364806e77c2915b1c3e03bf9bd90dccd"
            },
            {
              "fixed": "b3621031661ed10d6af511d7c41f512075357a00"
            },
            {
              "fixed": "c5970d3ee25b457ad2d78fe6e9662a12dae577cd"
            },
            {
              "fixed": "dd86461b71ff4a4f5194205896ae5f48f144240d"
            }
          ],
          "repo": "https://github.com/opensips/opensips",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-gx83-2gh8-7v56"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-121"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45809.json"
  },
  "details": "OpenSIPS is a Session Initiation Protocol (SIP) server implementation. Versions prior to 3.6.6 and 4.0.0-rc1 contain a denial of service vulnerability in the watcherinfo generation functionality. An attacker can create an oversized watcher entry by sending a SUBSCRIBE Event: presence request with a long From URI, and then trigger presence.winfo watcherinfo XML generation for the same presentity. OpenSIPS copies the stored watcher URI into a fixed-size stack buffer, overflowing it and crashing the process. A remote attacker can crash an OpenSIPS worker in deployments that expose handle_subscribe() and allow watcherinfo (presence.winfo) generation. The issue is configuration-dependent because the presence and presence_xml modules must be loaded and SUBSCRIBE routing must be reachable. This issue has been fixed in versions 3.6.6 and 4.0.0-rc1.",
  "id": "CVE-2026-45809",
  "modified": "2026-08-07T11:31:03.832710927Z",
  "published": "2026-08-04T23:30:03.111Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45809.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/OpenSIPS/opensips/security/advisories/GHSA-gx83-2gh8-7v56"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-45809"
    },
    {
      "type": "FIX",
      "url": "https://github.com/OpenSIPS/opensips/commit/c5970d3ee25b457ad2d78fe6e9662a12dae577cd"
    },
    {
      "type": "FIX",
      "url": "https://github.com/OpenSIPS/opensips/commit/dd86461b71ff4a4f5194205896ae5f48f144240d"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "OpenSIPS: Denial of Service in watcherinfo XML generation from oversized watcher URI"
}