Allocation of Resources Without Limits or Throttling in ISC BIND - CVE-2026-19630
Published: October 21, 2026
Vulnerability identifier: #VU156714
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-19630
CWE-ID: CWE-770
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service through CPU and/or memory exhaustion.
The vulnerability exists due to resource consumption without imposed limits in the BIND resolver's inbound DNS message processing when handling messages containing structures that trigger additional processing. A remote attacker can send a specially crafted DNS message containing a maliciously large number of these structures to exhaust CPU time and/or memory and cause a denial of service.
Affected software
ISC BIND
How to mitigate CVE-2026-19630
Install security update from vendor's website.
ISC BIND - addressed in versions 9.20.30, 9.20.30-s1, 9.21.27