CVE-2026-3591
published 2026-03-25CVE-2026-3591: 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…
medium5.4CVSS 3.1
AVNACLPRLUINSUCLILAN
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.
Affected
14 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | bind9 | < bind9 1:9.20.21-1 (forky) | bind9 1:9.20.21-1 (forky) |
| isc | bind | >= 0 < 9.20.21-r0 | 9.20.21-r0 |
| isc | bind | >= 0 < 9.20.21-r0 | 9.20.21-r0 |
| isc | bind | >= 9.20.0 < 9.20.21 | 9.20.21 |
| isc | bind | >= 9.21.0 < 9.21.20 | 9.21.20 |
| isc | bind9 | >= 0 < 1:9.20.21-1~deb13u1 | 1:9.20.21-1~deb13u1 |
| isc | bind9 | >= 0 < 1:9.20.21-1 | 1:9.20.21-1 |
| isc | bind9 | >= 0 < 1:9.18.39-0ubuntu0.22.04.3 | 1:9.18.39-0ubuntu0.22.04.3 |
| isc | bind9 | >= 0 < 1:9.18.39-0ubuntu0.24.04.3 | 1:9.18.39-0ubuntu0.24.04.3 |
| isc | bind9 | >= 0 < 1:9.20.11-1ubuntu2.2 | 1:9.20.11-1ubuntu2.2 |
| isc | bind_9 | 9.20.0 – 9.20.20 | — |
| isc | bind_9 | 9.20.9-S1 – 9.20.20-S1 | — |
| isc | bind_9 | 9.21.0 – 9.21.19 | — |
| msrc | azl3_bind_9.20.18-1_on_azure_linux_3.0 | — | — |
CVSS provenance
nvdv3.15.4MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
osv7.5HIGH