CVE-2026-81736

If a BIND resolver has cached a tree of SVCB/HTTPS AliasMode records, and is then queried for the root of that tree, the resolver will spend disproportionate CPU time constructing the response. 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-2026-81736

Configurations

No configuration.

History

26 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) Si un resolvedor BIND tiene en caché un árbol de registros SVCB/HTTPS AliasMode y luego se le consulta por la raíz de ese árbol, el resolvedor gastará un tiempo de CPU desproporcionado construyendo la respuesta. \nEste problema afecta a BIND?9 desde la versión?9.18.0 hasta la versión?9.18.50 incluida, desde la versión?9.20.0 hasta la versión?9.20.27 incluida, desde la versión?9.21.0 hasta la versión?9.21.25 incluida, desde la versión?9.18.11?S1 hasta la versión?9.18.50?S1 incluida, y desde la versión?9.20.9?S1 hasta la versión?9.20.27?S1 incluida.

16 Sep 2026, 14:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-16 14:17

Updated : 2026-10-26 21:10

NVD link : CVE-2026-81736

Mitre link : CVE-2026-81736

CVE.ORG link : CVE-2026-81736

JSON object : View

Products Affected

No product.

CWE

CWE-1050

Excessive Platform Resource Consumption within a Loop

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