{
  "threat_severity" : "Important",
  "public_date" : "2026-05-09T00:00:00Z",
  "bugzilla" : {
    "description" : "dnsmasq: extract_addresses() OOB read via malformed rdlen",
    "id" : "2458521",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2458521"
  },
  "cvss3" : {
    "cvss3_base_score" : "7.5",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-125",
  "details" : [ "A buffer overflow in dnsmasq’s extract_addresses() function allows an attacker to trigger a heap out-of-bounds read and crash by exploiting a malformed DNS response, enabling extract_name() to advance the pointer past the record’s end.", "A heap out-of-bounds read vulnerability was discovered in dnsmasq's DNS response processing. The extract_addresses() function trusts the declared record data length (rdlen) without verifying that a subsequent call to extract_name() stays within the record boundary. A crafted DNS response with a mismatched rdlen causes the remaining-bytes calculation to underflow, resulting in a massive out-of-bounds read and process crash." ],
  "statement" : "Red Hat rates this as Important. While this bug does not require any special dnsmasq configuration, the impact is limited to denial of service.",
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "release_date" : "2026-05-19T00:00:00Z",
    "advisory" : "RHSA-2026:19158",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10.2",
    "package" : "dnsmasq-0:2.90-7.el10_2"
  } ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Out of support scope",
    "package_name" : "dnsmasq",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Affected",
    "package_name" : "dnsmasq",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Affected",
    "package_name" : "dnsmasq",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Affected",
    "package_name" : "dnsmasq",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat OpenShift Container Platform 4",
    "fix_state" : "Affected",
    "package_name" : "rhcos",
    "cpe" : "cpe:/a:redhat:openshift:4"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-5172\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-5172\nhttps://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2026q2/018471.html" ],
  "name" : "CVE-2026-5172",
  "csaw" : false
}