CVE-2026-11605

The issue is a resource exhaustion vulnerability associated with DNSSEC validation. BIND always validates all RRSIG records in an answer, even if they are not strictly needed. A query to an authoritative server/zone which returns many valid but superfluous RRSIG records causes the validator to waste disproportionate CPU time. This issue affects BIND 9 versions 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, and 9.20.9-S1 through 9.20.24-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/bind9/9.20.26
https://downloads.isc.org/isc/bind9/9.21.24
https://kb.isc.org/docs/cve-2026-11605

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-22 15:16

Updated : 2026-07-22 20:33

NVD link : CVE-2026-11605

Mitre link : CVE-2026-11605

CVE.ORG link : CVE-2026-11605

JSON object : View

Products Affected

No product.

CWE

CWE-408

Incorrect Behavior Order: Early Amplification

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