CVE-2026-19941 MEDIUM

CVE-2026-19941: checkwildcard() accepts an out-of-zone NSEC as a wildcard-nonexistence proof

Vendor Isc
Product BIND 9
Weakness CWE-345
Published September 16, 2026
Last update September 16, 2026

CVSS base score

5.9/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Confidentiality None
Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

What the vulnerability does

01Description

An inapplicable NSEC record may be accepted by a `named` resolver as proof that no wildcard exists, which could allow an attacker at the same or an upstream level of the zone name to mask the existence of a victim's wildcard record. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.27-S1.

Key dates

02Disclosure timeline

September 16, 2026 CVE published

Related vulnerabilities

04Related CVE