CVE-2026-19666

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://downloads.isc.org/isc/bind9/9.20.29
https://downloads.isc.org/isc/bind9/9.21.26
https://kb.isc.org/docs/cve-2026-19666

Configurations

No configuration.

History

16 Sep 2026, 15:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-16 15:17

Updated : 2026-09-17 18:16

NVD link : CVE-2026-19666

Mitre link : CVE-2026-19666

CVE.ORG link : CVE-2026-19666

JSON object : View

Products Affected

No product.

CWE

CWE-416

Use After Free

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