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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-11721 Detail

Description

It is possible for an attacker's zone to respond to a query with an RRSIG that has a smaller number of labels than the zone in which the RRSIG is contained. This causes `named` to produce a wildcard name for a zone that is shorter than the attacker's zone, which can result in cache poisoning. For this attack to have any effect, the resolver under attack must have set `synth-from-dnssec yes;` (which is the default). This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://downloads.isc.org/isc/bind9/9.20.26 Internet Systems Consortium (ISC)
https://downloads.isc.org/isc/bind9/9.21.24 Internet Systems Consortium (ISC)
https://kb.isc.org/docs/cve-2026-11721 Internet Systems Consortium (ISC)

Weakness Enumeration

CWE-ID CWE Name Source
CWE-1284 Improper Validation of Specified Quantity in Input Internet Systems Consortium (ISC)  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-11721
NVD Published Date:
07/22/2026
NVD Last Modified:
07/22/2026
Source:
Internet Systems Consortium (ISC)