Description
The BIND resolver accepts validly-signed NSEC records where the "Next Domain Name" field points outside the signer's zone. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.
Affected products
isc: bind
References3
- kb.isc.org/docs/cve-2026-13321 Vendor Advisory
- downloads.isc.org/isc/bind9/9.20.26 Product
- downloads.isc.org/isc/bind9/9.21.24 Product
Metrics
- CVSS 3.1
-
8.6
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N - EPSS — exploit probability
- 0% percentile: 12 · as of 14 November 2026
- CWE
- CWE-346
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