Copyright © 2012 Red Hat, Inc. All rights reserved. Important 2026-05-21T12:15:50 bind: SIG(0) validation during query flood may lead to undefined behavior 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CWE-367

A flaw was found in BIND. A remote attacker could exploit a race condition during SIG(0) signature validation of an incoming DNS message. If the "recursive-clients" limit is reached and the message is discarded, a use-after-free vulnerability may occur. This could lead to undefined behavior and potentially result in a denial of service.

Important: A race condition in BIND's SIG(0) validation process can lead to undefined behavior and a denial of service when the server is under a query flood and processing signed DNS messages. This flaw could disrupt critical DNS resolution services in Red Hat environments. Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability. Red Hat Hardened Images 2026-04-10T00:00:00Z RHSA-2026:7412 bind-main-9.18.48-1.1.hum1 Red Hat Enterprise Linux 10 Not affected bind Red Hat Enterprise Linux 6 Not affected bind Red Hat Enterprise Linux 7 Not affected bind Red Hat Enterprise Linux 8 Not affected bind Red Hat Enterprise Linux 8 Not affected bind9.16 Red Hat Enterprise Linux 9 Not affected bind Red Hat Enterprise Linux 9 Not affected bind9.18 Red Hat Enterprise Linux 9 Not affected dhcp Red Hat OpenShift Container Platform 4 Affected rhcos https://www.cve.org/CVERecord?id=CVE-2026-5947 https://nvd.nist.gov/vuln/detail/CVE-2026-5947