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.
References
| Link | Resource |
|---|---|
| https://downloads.isc.org/isc/bind9/9.20.21 | Patch |
| https://downloads.isc.org/isc/bind9/9.21.20 | Patch |
| https://kb.isc.org/docs/cve-2026-3591 | Vendor Advisory |
Configurations
History
21 May 2026, 15:24
| Type | Values Removed | Values Added |
|---|---|---|
| CPE | cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:* | |
| Summary |
|
|
| First Time |
Isc bind
Isc |
|
| References | () https://downloads.isc.org/isc/bind9/9.20.21 - Patch | |
| References | () https://downloads.isc.org/isc/bind9/9.21.20 - Patch | |
| References | () https://kb.isc.org/docs/cve-2026-3591 - Vendor Advisory |
25 Mar 2026, 14:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-03-25 14:16
Updated : 2026-05-21 15:24
NVD link : CVE-2026-3591
Mitre link : CVE-2026-3591
CVE.ORG link : CVE-2026-3591
JSON object : View
Products Affected
isc
- bind
