Vulnerability · Published Sep 16, 2026 · Assigned by isc

CVE-2026-19662qpcache NOQNAME proof use-after-free crashes recursive resolver

Medium 5.9

In plain English

A medium-severity use-after-free in BIND 9 from ISC. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 40% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)5.9Medium
Exploit odds (30 days)0.5%top 59.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

An attacker may be able to cause a `named` resolver to abort. The attack requires inducing the victim resolver to send multiple queries for a DNSSEC-signed zone hosted by an authoritative server under the control of the attacker. If the auth responds with a particular sequence of crafted answers, and those answers arrive in a particular order with particular timing, the `named` resolver will encounter a use-after-free bug, and abort. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.27, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.27-S1.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:10bind32:9.18.33-15.el10_2.13ALSA-2026:90328
AlmaLinux:8bind32:9.11.36-18.el8_10ALSA-2026:93925
AlmaLinux:9bind32:9.16.23-40.el9_8.12ALSA-2026:89745
AlmaLinux:10bind-chroot32:9.18.33-15.el10_2.13ALSA-2026:90328
AlmaLinux:8bind-chroot32:9.11.36-18.el8_10ALSA-2026:93925
AlmaLinux:9bind-chroot32:9.16.23-40.el9_8.12ALSA-2026:89745
AlmaLinux:10bind-devel32:9.18.33-15.el10_2.13ALSA-2026:90328
AlmaLinux:8bind-devel32:9.11.36-18.el8_10ALSA-2026:93925
AlmaLinux:9bind-devel32:9.16.23-40.el9_8.12ALSA-2026:89745
AlmaLinux:9bind-dnssec-doc32:9.16.23-40.el9_8.12ALSA-2026:89745
AlmaLinux:10bind-dnssec-utils32:9.18.33-15.el10_2.13ALSA-2026:90328
AlmaLinux:9bind-dnssec-utils32:9.16.23-40.el9_8.12ALSA-2026:89745
AlmaLinux:10bind-doc32:9.18.33-15.el10_2.13ALSA-2026:90328
AlmaLinux:9bind-doc32:9.16.23-40.el9_8.12ALSA-2026:89745
AlmaLinux:8bind-export-devel32:9.11.36-18.el8_10ALSA-2026:93925
AlmaLinux:8bind-export-libs32:9.11.36-18.el8_10ALSA-2026:93925
AlmaLinux:10bind-libs32:9.18.33-15.el10_2.13ALSA-2026:90328
AlmaLinux:8bind-libs32:9.11.36-18.el8_10ALSA-2026:93925
AlmaLinux:9bind-libs32:9.16.23-40.el9_8.12ALSA-2026:89745
AlmaLinux:8bind-libs-lite32:9.11.36-18.el8_10ALSA-2026:93925
AlmaLinux:10bind-license32:9.18.33-15.el10_2.13ALSA-2026:90328
AlmaLinux:8bind-license32:9.11.36-18.el8_10ALSA-2026:93925
AlmaLinux:9bind-license32:9.16.23-40.el9_8.12ALSA-2026:89745
AlmaLinux:8bind-lite-devel32:9.11.36-18.el8_10ALSA-2026:93925
AlmaLinux:8bind-pkcs1132:9.11.36-18.el8_10ALSA-2026:93925
AlmaLinux:8bind-pkcs11-devel32:9.11.36-18.el8_10ALSA-2026:93925
AlmaLinux:8bind-pkcs11-libs32:9.11.36-18.el8_10ALSA-2026:93925
AlmaLinux:8bind-pkcs11-utils32:9.11.36-18.el8_10ALSA-2026:93925
AlmaLinux:8bind-sdb32:9.11.36-18.el8_10ALSA-2026:93925
AlmaLinux:8bind-sdb-chroot32:9.11.36-18.el8_10ALSA-2026:93925
AlmaLinux:10bind-utils32:9.18.33-15.el10_2.13ALSA-2026:90328
AlmaLinux:8bind-utils32:9.11.36-18.el8_10ALSA-2026:93925
AlmaLinux:9bind-utils32:9.16.23-40.el9_8.12ALSA-2026:89745
AlmaLinux:8bind9.1632:9.16.23-0.22.el8_10.21ALSA-2026:94011
AlmaLinux:8bind9.16-chroot32:9.16.23-0.22.el8_10.21ALSA-2026:94011
AlmaLinux:8bind9.16-devel32:9.16.23-0.22.el8_10.21ALSA-2026:94011
AlmaLinux:8bind9.16-dnssec-utils32:9.16.23-0.22.el8_10.21ALSA-2026:94011
AlmaLinux:8bind9.16-doc32:9.16.23-0.22.el8_10.21ALSA-2026:94011
AlmaLinux:8bind9.16-libs32:9.16.23-0.22.el8_10.21ALSA-2026:94011
AlmaLinux:8bind9.16-license32:9.16.23-0.22.el8_10.21ALSA-2026:94011
AlmaLinux:8bind9.16-utils32:9.16.23-0.22.el8_10.21ALSA-2026:94011
AlmaLinux:9bind9.1832:9.18.29-14.el9_8.11ALSA-2026:89746
AlmaLinux:9bind9.18-chroot32:9.18.29-14.el9_8.11ALSA-2026:89746
AlmaLinux:9bind9.18-devel32:9.18.29-14.el9_8.11ALSA-2026:89746
AlmaLinux:9bind9.18-dnssec-utils32:9.18.29-14.el9_8.11ALSA-2026:89746
AlmaLinux:9bind9.18-doc32:9.18.29-14.el9_8.11ALSA-2026:89746
AlmaLinux:9bind9.18-libs32:9.18.29-14.el9_8.11ALSA-2026:89746
AlmaLinux:9bind9.18-utils32:9.18.29-14.el9_8.11ALSA-2026:89746
AlmaLinux:8python3-bind32:9.11.36-18.el8_10ALSA-2026:93925
AlmaLinux:9python3-bind32:9.16.23-40.el9_8.12ALSA-2026:89745
AlmaLinux:8python3-bind9.1632:9.16.23-0.22.el8_10.21ALSA-2026:94011
Alpine:v3.22bind9.20.29-r0ALPINE-CVE-2026-19662
Alpine:v3.23bind9.20.29-r0ALPINE-CVE-2026-19662
Alpine:v3.24bind9.20.29-r0ALPINE-CVE-2026-19662
Debian:12bind91:9.18.49-1~deb12u3DEBIAN-CVE-2026-19662
Debian:13bind91:9.20.29-1~deb13u1DEBIAN-CVE-2026-19662
Debian:14bind91:9.20.29-1DEBIAN-CVE-2026-19662
Rocky Linux:10bind2:9.18.33-15.el10_2.13RLSA-2026:90328
Rocky Linux:8bind2:9.11.36-18.el8_10RLSA-2026:93925
Rocky Linux:9bind2:9.16.23-40.el9_8.12RLSA-2026:89745
Rocky Linux:8bind9.162:9.16.23-0.22.el8_10.21RLSA-2026:94011
Rocky Linux:9bind9.182:9.18.29-14.el9_8.11RLSA-2026:89746
Ubuntu:22.04:LTSbind91:9.18.39-0ubuntu0.22.04.7USN-8929-1
Ubuntu:22.04:LTSbind91:9.18.39-0ubuntu0.22.04.8USN-8969-1
Ubuntu:22.04:LTSbind91:9.18.39-0ubuntu0.22.04.7UBUNTU-CVE-2026-19662
Ubuntu:24.04:LTSbind91:9.18.39-0ubuntu0.24.04.8UBUNTU-CVE-2026-19662
Ubuntu:24.04:LTSbind91:9.18.39-0ubuntu0.24.04.8USN-8929-1
Ubuntu:24.04:LTSbind91:9.18.39-0ubuntu0.24.04.9USN-8969-1
Ubuntu:26.04:LTSbind91:9.20.24-1ubuntu0.4UBUNTU-CVE-2026-19662
Ubuntu:26.04:LTSbind91:9.20.24-1ubuntu0.4USN-8929-1
Ubuntu:26.04:LTSbind91:9.20.24-1ubuntu0.5USN-8969-1
Ubuntu:26.10bind91:9.20.24-1ubuntu3.1USN-8969-1
Ubuntu:26.10bind91:9.20.24-1ubuntu3.1UBUNTU-CVE-2026-19662
Ubuntu:22.04:LTSbind9-libsno fix listedUBUNTU-CVE-2026-19662
Ubuntu:24.04:LTSisc-dhcpno fix listedUBUNTU-CVE-2026-19662
Ubuntu:26.04:LTSisc-dhcpno fix listedUBUNTU-CVE-2026-19662

Affected products (as reported)

VendorProductVersions
ISC BIND 9 9.11.0 – through 9.18.509.20.0 – through 9.20.279.11.3-S1 – through 9.18.50-S19.20.9-S1 – through 9.20.27-S1

Weakness: CWE-416 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

References