CVE-2026-19666
Published:September 16, 2026
Updated:September 22, 2026
On a resolver configured to use "dns64", if an applicable answer from the authoritative server is malformed in a specific way, the resolver "named" process will exit unexpectedly.
This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.27-S1.
Affected Packages
https://github.com/isc-projects/bind9.git (GITHUB):
Affected version(s) >=v9.21.0 <v9.21.26Fix Suggestion:
Update to version v9.21.26https://github.com/isc-projects/bind9.git (GITHUB):
Affected version(s) >=v9.20.0 <v9.20.29Fix Suggestion:
Update to version v9.20.29Additional Notes
The description of this vulnerability differs from MITRE.
Related Resources (4)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.7
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
NONE
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Weakness Type (CWE)
Use After Free
EPSS
Base Score:
0.48