Buffer overflow in ISC BIND - CVE-2026-94300
Published: October 21, 2026
Vulnerability identifier: #VU156713
CSH Severity: High
CVSS v4: 9.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-94300
CWE-ID: CWE-119
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service and potentially execute arbitrary code.
The vulnerability exists due to memory corruption in the GSS-TSIG message handling of ISC BIND's named process when concurrently processing replayed signed UDP messages. A remote attacker can capture and replay a previously signed UDP message while the negotiated TSIG key remains valid to cause the process to abort, and additionally send crafted queries to a zone under their control to potentially execute arbitrary code.
Affected software
ISC BIND
How to mitigate CVE-2026-94300
Install security update from vendor's website.
ISC BIND - addressed in versions 9.20.30, 9.20.30-s1, 9.21.27