CVE-2026-19941

checkwildcard() accepts an out-of-zone NSEC as a wildcard-nonexistence proof

At a glance

Severity: MEDIUM 5.9
EPSS: EPSS 0.23 % · percentile 13 (2026-10-27)
State: PUBLISHED
Published: 2026-09-16
Updated: 2026-09-17
Assigner: isc
NVD status: Awaiting Analysis

Description

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.

Scores

Version	Score	Vector	Scored by
CVSS 3.1	MEDIUM 5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N	isc
CVSS 3.1	MEDIUM 5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N	NVD · security-officer@isc.org (Secondary)

Weaknesses (CWE)

CWE-345

European references

ENISA EUVD · EUVD-2026-80745
GCVE · GCVE-0-2026-19941

CERT-FR advisories

CERTFR-2026-AVI-1385 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
CERTFR-2026-AVI-1376 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr

Affected products

Product	Versions
ISC · BIND 9	affected 9.11.0 ≤ 9.18.50 ; affected 9.20.0 ≤ 9.20.27 ; affected 9.21.0 ≤ 9.21.25 ; affected 9.11.3-S1 ≤ 9.18.50-S1 ; affected 9.20.9-S1 ≤ 9.20.27-S1

References

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
EPSS (FIRST.org)	FIRST — attribution requested
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)	Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD