CVE-2026-3591
Published: Mar 25, 2026
Modified: Mar 25, 2026
CVSS v3.1
5.4
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.
| Vendor | Product | Versions |
|---|---|---|
ISC | BIND 9 | affected 9.20.0 - <= 9.20.20affected 9.21.0 - <= 9.21.19affected 9.20.9-S1 - <= 9.20.20-S1unaffected 9.18.0 - <= 9.18.46unaffected 9.18.11-S1 - <= 9.18.46-S1 |
CVSS v3.1 Details
CVSS v3.1 Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
References
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