{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "5e35941d990123f155b02d5663e51a24f816b6f3"
            },
            {
              "fixed": "a2cd54b9348e485d338b3c132338a4410c99afaf"
            },
            {
              "fixed": "c95dc674ebf01ecfb40388b6facfc89b81fed3b7"
            },
            {
              "fixed": "41b417ff73a24b2c68134992cc44c88db27f482d"
            },
            {
              "fixed": "52235bf88159a1ef16434ab49e47e99c8a09ab20"
            },
            {
              "fixed": "774a434f8c9c8602a976b2536f65d0172a07f4d2"
            },
            {
              "fixed": "6bce72daeccca9aa1746e92d6c3d4784e71f2ebb"
            },
            {
              "fixed": "fb6c3596823ec5dd09c2123340330d7448f51a59"
            },
            {
              "fixed": "1e3a3593162c96e8a8de48b1e14f60c3b57fca8a"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.6.17"
            },
            {
              "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-2026-23456.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_conntrack_h323: fix OOB read in decode_int() CONS case\n\nIn decode_int(), the CONS case calls get_bits(bs, 2) to read a length\nvalue, then calls get_uint(bs, len) without checking that len bytes\nremain in the buffer. The existing boundary check only validates the\n2 bits for get_bits(), not the subsequent 1-4 bytes that get_uint()\nreads. This allows a malformed H.323/RAS packet to cause a 1-4 byte\nslab-out-of-bounds read.\n\nAdd a boundary check for len bytes after get_bits() and before\nget_uint().",
  "id": "CVE-2026-23456",
  "modified": "2026-07-08T05:38:01.525788880Z",
  "published": "2026-04-03T15:15:37.534Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1e3a3593162c96e8a8de48b1e14f60c3b57fca8a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/41b417ff73a24b2c68134992cc44c88db27f482d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/52235bf88159a1ef16434ab49e47e99c8a09ab20"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6bce72daeccca9aa1746e92d6c3d4784e71f2ebb"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/774a434f8c9c8602a976b2536f65d0172a07f4d2"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a2cd54b9348e485d338b3c132338a4410c99afaf"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c95dc674ebf01ecfb40388b6facfc89b81fed3b7"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/fb6c3596823ec5dd09c2123340330d7448f51a59"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23456.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-23456"
    },
    {
      "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:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "netfilter: nf_conntrack_h323: fix OOB read in decode_int() CONS case"
}