CVE-2026-81563

A BIND resolver encountering an SVCB/HTTPS AliasMode record referencing 14 or more SVCB/HTTPS ServiceMode records may fail to properly deallocate internal resources. If this happens repeatedly, resource exhaustion will eventually prevent the resolver from performing new recursive lookups. This issue affects BIND 9 versions 9.18.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.18.11-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-2026-81563

Configurations

No configuration.

History

16 Sep 2026, 14:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-16 14:17

Updated : 2026-09-17 18:17

NVD link : CVE-2026-81563

Mitre link : CVE-2026-81563

CVE.ORG link : CVE-2026-81563

JSON object : View

Products Affected

No product.

CWE

CWE-401

Missing Release of Memory after Effective Lifetime

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