{
  "threat_severity" : "Important",
  "public_date" : "2026-07-22T00:00:00Z",
  "bugzilla" : {
    "description" : "bind: bind9: Cache poisoning via label count discrepancy, RRSIG, wildcards",
    "id" : "2504338",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2504338"
  },
  "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:H/A:N",
    "status" : "verified"
  },
  "cwe" : "CWE-345",
  "details" : [ "It is possible for an attacker's zone to respond to a query with an RRSIG that has a smaller number of labels than the zone in which the RRSIG is contained. This causes `named` to produce a wildcard name for a zone that is shorter than the attacker's zone, which can result in cache poisoning. For this attack to have any effect, the resolver under attack must have set `synth-from-dnssec yes;` (which is the default).\nThis issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.", "It is possible for an attacker's zone to respond to a query with an RRSIG that has a smaller number of labels than the zone in which the RRSIG is contained. This causes named to produce a wildcard name for a zone that is shorter than the attacker's zone, which can result in cache poisoning. For this attack to have any effect, the resolver under attack must have set synth-from-dnssec yes; (which is the default)." ],
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "release_date" : "2026-08-17T00:00:00Z",
    "advisory" : "RHSA-2026:55437",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10.2",
    "package" : "bind-32:9.18.33-15.el10_2.10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7 Extended Lifecycle Support",
    "release_date" : "2026-08-26T00:00:00Z",
    "advisory" : "RHSA-2026:60383",
    "cpe" : "cpe:/o:redhat:rhel_els:7",
    "package" : "bind-32:9.11.4-26.P2.el7_9.21"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2026-08-13T00:00:00Z",
    "advisory" : "RHSA-2026:54509",
    "cpe" : "cpe:/a:redhat:enterprise_linux:8",
    "package" : "bind9.16-32:9.16.23-0.22.el8_10.12"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2026-08-13T00:00:00Z",
    "advisory" : "RHSA-2026:54654",
    "cpe" : "cpe:/a:redhat:enterprise_linux:8",
    "package" : "bind-32:9.11.36-16.el8_10.14"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2026-08-13T00:00:00Z",
    "advisory" : "RHSA-2026:54654",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8",
    "package" : "bind-32:9.11.36-16.el8_10.14"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2026-08-13T00:00:00Z",
    "advisory" : "RHSA-2026:54510",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "bind-32:9.16.23-40.el9_8.8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2026-08-17T00:00:00Z",
    "advisory" : "RHSA-2026:55442",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "bind9.18-32:9.18.29-14.el9_8.8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions",
    "release_date" : "2026-08-19T00:00:00Z",
    "advisory" : "RHSA-2026:57189",
    "cpe" : "cpe:/a:redhat:rhel_e4s:9.4",
    "package" : "bind-32:9.16.23-18.el9_4.12"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.6 Extended Update Support",
    "release_date" : "2026-08-17T00:00:00Z",
    "advisory" : "RHSA-2026:55441",
    "cpe" : "cpe:/a:redhat:rhel_eus:9.6",
    "package" : "bind-32:9.16.23-31.el9_6.4"
  }, {
    "product_name" : "Red Hat OpenShift Container Platform 4.22",
    "release_date" : "2026-08-25T00:00:00Z",
    "advisory" : "RHSA-2026:57362",
    "cpe" : "cpe:/a:redhat:openshift:4.22::el9",
    "package" : "rhcos-4.22.9.8.202608191915-0"
  }, {
    "product_name" : "Red Hat Hardened Images",
    "release_date" : "2026-08-12T00:00:00Z",
    "advisory" : "RHSA-2026:54071",
    "cpe" : "cpe:/a:redhat:hummingbird:1",
    "package" : "bind-main-9.20.26-0.1.hum1",
    "impact" : "important"
  } ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Affected",
    "package_name" : "bind",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "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" : "Affected",
    "package_name" : "openshift/ose-rhel-coreos-8",
    "cpe" : "cpe:/a:redhat:openshift:4"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-11721\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-11721" ],
  "name" : "CVE-2026-11721",
  "csaw" : false
}