{
  "threat_severity" : "Moderate",
  "public_date" : "2026-04-03T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: netfilter: nf_conntrack_h323: fix OOB read in decode_int() CONS case",
    "id" : "2454851",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2454851"
  },
  "cvss3" : {
    "cvss3_base_score" : "6.4",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:H",
    "status" : "draft"
  },
  "cwe" : "CWE-125",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nnetfilter: nf_conntrack_h323: fix OOB read in decode_int() CONS case\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.\nAdd a boundary check for len bytes after get_bits() and before\nget_uint().", "A flaw was found in the Linux kernel's netfilter H.323 connection tracking module. A remote attacker could exploit this vulnerability by sending a specially crafted H.323/RAS (H.323 Registration, Admission, and Status) packet. The system's processing of these packets could lead to an out-of-bounds read of 1-4 bytes, potentially causing information disclosure or a denial of service (DoS)." ],
  "statement" : "This vulnerability is remotely exploitable via malformed H.323/RAS network packets. However, exploitation requires the nf_conntrack_h323 module to be loaded, which is only needed for H.323 VoIP traffic traversing NAT. The out-of-bounds read is limited to 1-4 bytes and most likely causes a crash rather than meaningful data leakage.",
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Out of support scope",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-23456\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-23456\nhttps://lore.kernel.org/linux-cve-announce/2026040318-CVE-2026-23456-7da2@gregkh/T" ],
  "name" : "CVE-2026-23456",
  "mitigation" : {
    "value" : "To mitigate this issue, prevent the nf_conntrack_h323 module from being loaded. See https://access.redhat.com/solutions/41278 for instructions. This will disable H.323 connection tracking for NAT.",
    "lang" : "en:us"
  },
  "csaw" : false
}