{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "f5b321bd37fbec9188feb1f721ab46a5ac0b35da"
            },
            {
              "fixed": "ed81b6a7012485acdb9c6c80735a0b7d8e5e1873"
            },
            {
              "fixed": "cd1b7403ec835f8a0b3f1f7e68ac26af2cb1e42f"
            },
            {
              "fixed": "b75209debb9adab287b3caa982f77788c1e15027"
            },
            {
              "fixed": "528b4509c9dfc272e2e92d811915e5211650d383"
            },
            {
              "fixed": "75fcaee5170e7dbbee778927134ef2e9568b4659"
            },
            {
              "fixed": "865dba58958c3a86786f89a501971ab0e3ec6ba9"
            },
            {
              "fixed": "d4f17256544cc37f6534a14a27a9dec3540c2015"
            },
            {
              "fixed": "fbce58e719a17aa215c724473fd5baaa4a8dc57c"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.6.34"
            },
            {
              "fixed": "5.10.253"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.203"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.167"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.130"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.78"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.20"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "6.19.10"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23457.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_conntrack_sip: fix Content-Length u32 truncation in sip_help_tcp()\n\nsip_help_tcp() parses the SIP Content-Length header with\nsimple_strtoul(), which returns unsigned long, but stores the result in\nunsigned int clen.  On 64-bit systems, values exceeding UINT_MAX are\nsilently truncated before computing the SIP message boundary.\n\nFor example, Content-Length 4294967328 (2^32 + 32) is truncated to 32,\ncausing the parser to miscalculate where the current message ends.  The\nloop then treats trailing data in the TCP segment as a second SIP\nmessage and processes it through the SDP parser.\n\nFix this by changing clen to unsigned long to match the return type of\nsimple_strtoul(), and reject Content-Length values that exceed the\nremaining TCP payload length.",
  "id": "CVE-2026-23457",
  "modified": "2026-07-08T05:39:02.490490906Z",
  "published": "2026-04-03T15:15:38.193Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/528b4509c9dfc272e2e92d811915e5211650d383"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/75fcaee5170e7dbbee778927134ef2e9568b4659"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/865dba58958c3a86786f89a501971ab0e3ec6ba9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b75209debb9adab287b3caa982f77788c1e15027"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/cd1b7403ec835f8a0b3f1f7e68ac26af2cb1e42f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d4f17256544cc37f6534a14a27a9dec3540c2015"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ed81b6a7012485acdb9c6c80735a0b7d8e5e1873"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/fbce58e719a17aa215c724473fd5baaa4a8dc57c"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23457.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-23457"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.5",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "netfilter: nf_conntrack_sip: fix Content-Length u32 truncation in sip_help_tcp()"
}