{
  "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": "4d23613b"
            },
            {
              "fixed": "5f103eff"
            }
          ],
          "repo": "https://github.com/opensips/opensips",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-jv35-555v-54jh"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-190"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45103.json"
  },
  "details": "OpenSIPS is a Session Initiation Protocol (SIP) server implementation. In versions prior to 3.6.6 and 4.0.0-rc1, the TCP message framing layer parses the Content-Length header using unsigned int arithmetic with no overflow check. When an attacker sends a Content-Length value that overflows unsigned int (e.g., 4294967296), the framing layer computes a wrapped-around value (e.g., 0) and splits the TCP stream at the wrong boundary, causing the body of the first SIP message to be processed as a separate message and enabling SIP message smuggling. Because Content-Length is parsed in the transport layer before authentication, an unauthenticated, network-based attacker can smuggle arbitrary SIP messages over any TCP-based transport (proto_tcp, proto_tls, proto_ws, proto_wss) on any instance with TCP enabled, with no routing-script preconditions. This allows smuggled messages to bypass front-end SBC/proxy security policies, inherit the connection's authentication context, and evade rate limiting. This issue has been fixed in versions 3.6.6 and 4.0.0-rc1.",
  "id": "CVE-2026-45103",
  "modified": "2026-08-12T03:51:20.191930492Z",
  "published": "2026-08-04T21:56:57.422Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45103.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/OpenSIPS/opensips/security/advisories/GHSA-jv35-555v-54jh"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-45103"
    },
    {
      "type": "FIX",
      "url": "https://github.com/OpenSIPS/opensips/commit/4d23613b"
    },
    {
      "type": "FIX",
      "url": "https://github.com/OpenSIPS/opensips/commit/5f103eff"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "OpenSIPS: SIP Message Smuggling via TCP Content-Length Integer Overflow"
}