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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-3591 Detail

Description

A use-after-return vulnerability exists in the `named` server when handling DNS queries signed with SIG(0). Using a specially-crafted DNS request, an attacker may be able to cause an ACL to improperly (mis)match an IP address. In a default-allow ACL (denying only specific IP addresses), this may lead to unauthorized access. Default-deny ACLs should fail-secure. This issue affects BIND 9 versions 9.20.0 through 9.20.20, 9.21.0 through 9.21.19, and 9.20.9-S1 through 9.20.20-S1. BIND 9 versions 9.18.0 through 9.18.46 and 9.18.11-S1 through 9.18.46-S1 are NOT affected.


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/bind9/9.20.21 Internet Systems Consortium (ISC)
https://downloads.isc.org/isc/bind9/9.21.20 Internet Systems Consortium (ISC)
https://kb.isc.org/docs/cve-2026-3591 Internet Systems Consortium (ISC)

Weakness Enumeration

CWE-ID CWE Name Source
CWE-305 Authentication Bypass by Primary Weakness Internet Systems Consortium (ISC)  
CWE-562 Return of Stack Variable Address Internet Systems Consortium (ISC)  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-3591
NVD Published Date:
03/25/2026
NVD Last Modified:
03/25/2026
Source:
Internet Systems Consortium (ISC)