{
  "threat_severity" : "Important",
  "public_date" : "2026-03-25T13:29:19Z",
  "bugzilla" : {
    "description" : "bind: BIND: Denial of Service via specially crafted domain query causing a memory leak",
    "id" : "2451310",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2451310"
  },
  "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-772",
  "details" : [ "A specially crafted domain can be used to cause a memory leak in a BIND resolver simply by querying this domain.\nThis issue affects BIND 9 versions 9.20.0 through 9.20.20, 9.21.0 through 9.21.19, and 9.20.9-S1 through 9.20.20-S1.\nBIND 9 versions 9.18.0 through 9.18.46 and 9.18.11-S1 through 9.18.46-S1 are NOT affected.", "A flaw was found in the BIND resolver. A remote attacker can exploit this vulnerability by querying a specially crafted domain, which causes a memory leak. This memory leak can lead to a Denial of Service (DoS) condition, making the BIND resolver unavailable to legitimate users." ],
  "statement" : "This is an Important denial of service flaw in BIND 9. A remote attacker can trigger a memory leak in the BIND resolver by sending a specially crafted domain query, potentially exhausting system resources. Red Hat Enterprise Linux versions shipping BIND 9.18 are not affected by this vulnerability.",
  "affected_release" : [ {
    "product_name" : "Red Hat Hardened Images",
    "release_date" : "2026-04-07T00:00:00Z",
    "advisory" : "RHSA-2026:6935",
    "cpe" : "cpe:/a:redhat:hummingbird:1",
    "package" : "bind-main-9.18.48-1.hum1"
  } ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Not affected",
    "package_name" : "bind",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Not affected",
    "package_name" : "bind",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "bind",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Not affected",
    "package_name" : "bind",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Not affected",
    "package_name" : "bind9.16",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Not affected",
    "package_name" : "bind",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Not affected",
    "package_name" : "bind9.18",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Not affected",
    "package_name" : "dhcp",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat OpenShift Container Platform 4",
    "fix_state" : "Not affected",
    "package_name" : "rhcos",
    "cpe" : "cpe:/a:redhat:openshift:4"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-3104\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-3104\nhttps://downloads.isc.org/isc/bind9/9.20.21\nhttps://downloads.isc.org/isc/bind9/9.21.20\nhttps://kb.isc.org/docs/cve-2026-3104" ],
  "name" : "CVE-2026-3104",
  "mitigation" : {
    "value" : "To mitigate this issue, restrict access to the BIND resolver to trusted clients only. This can be achieved by configuring firewall rules to limit inbound connections to port 53 (UDP/TCP) from known, authorized IP addresses or networks. Alternatively, configure BIND to listen only on specific trusted interfaces or localhost.\nExample using firewalld:\n`firewall-cmd --permanent --add-rich-rule='rule family=\"ipv4\" source address=\"<TRUSTED_IP_OR_NETWORK>\" port port=53 protocol=\"udp\" accept'`\n`firewall-cmd --permanent --add-rich-rule='rule family=\"ipv4\" source address=\"<TRUSTED_IP_OR_NETWORK>\" port port=53 protocol=\"tcp\" accept'`\n`firewall-cmd --reload`\nAfter applying changes, a restart of the BIND service may be required for the new configuration to take full effect. This may temporarily interrupt DNS resolution services.",
    "lang" : "en:us"
  },
  "csaw" : false
}