CVE-2026-3591
MEDIUM
5,4
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: low
User Interaction: none
Scope: unchanged
Confidentiality: low
Integrity: low
Availability: none
Description
AI Translation Available
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.
305
Authentication Bypass by Primary Weakness
DraftCommon Consequences
Security Scopes Affected:
Access Control
Potential Impacts:
Bypass Protection Mechanism
Applicable Platforms
All platforms may be affected
562
Return of Stack Variable Address
DraftCommon Consequences
Security Scopes Affected:
Availability
Integrity
Confidentiality
Potential Impacts:
Read Memory
Modify Memory
Execute Unauthorized Code Or Commands
Dos: Crash, Exit, Or Restart
Applicable Platforms
Languages:
C, C++
https://downloads.isc.org/isc/bind9/9.20.21
https://downloads.isc.org/isc/bind9/9.21.20
https://kb.isc.org/docs/cve-2026-3591