Vulnerability · Published Sep 16, 2026 · Assigned by isc

CVE-2026-77692Unauthenticated remote crash of named via a single DoH SIG(0) request

High 7.5

In plain English

A high-severity null pointer dereference 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 6.6% (higher than 94% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.5High
Exploit odds (30 days)6.6%top 6.2% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

An attacker can cause `named` to abort by sending a crafted DNS-over-HTTPS request with a cryptographically invalid SIG(0) record, and then closing the transport connection prematurely. This issue affects BIND 9 versions 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, and 9.20.9-S1 through 9.20.27-S1.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Alpine:v3.22bind9.20.29-r0ALPINE-CVE-2026-77692
Alpine:v3.23bind9.20.29-r0ALPINE-CVE-2026-77692
Alpine:v3.24bind9.20.29-r0ALPINE-CVE-2026-77692
Debian:12bind9no fix listedDEBIAN-CVE-2026-77692
Debian:13bind91:9.20.29-1~deb13u1DEBIAN-CVE-2026-77692
Debian:14bind91:9.20.29-1DEBIAN-CVE-2026-77692
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: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:LTSbind91:9.20.24-1ubuntu0.5USN-8969-1
Ubuntu:26.04:LTSbind91:9.20.24-1ubuntu0.4USN-8929-1
Ubuntu:26.04:LTSbind91:9.20.24-1ubuntu0.4UBUNTU-CVE-2026-77692
Ubuntu:26.10bind91:9.20.24-1ubuntu3.1UBUNTU-CVE-2026-77692
Ubuntu:26.10bind91:9.20.24-1ubuntu3.1USN-8969-1
Ubuntu:22.04:LTSbind9-libsno fix listedUBUNTU-CVE-2026-77692
Ubuntu:24.04:LTSisc-dhcpno fix listedUBUNTU-CVE-2026-77692
Ubuntu:26.04:LTSisc-dhcpno fix listedUBUNTU-CVE-2026-77692

Affected products (as reported)

VendorProductVersions
ISC BIND 9 9.20.0 – through 9.20.279.21.0 – through 9.21.259.20.9-S1 – through 9.20.27-S1

Weakness: CWE-476 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References