CVEvulnerability
CVE-2026-11721
7.5 HIGH
Official page ↗
- Status
- Undergoing Analysis
- Published
- 2026-07-22
- Last modified
- 2026-10-24
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 7.5 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- Weaknesses
- CWE-1284
Description
It is possible for an attacker's zone to respond to a query with an RRSIG that has a smaller number of labels than the zone in which the RRSIG is contained. This causes `named` to produce a wildcard name for a zone that is shorter than the attacker's zone, which can result in cache poisoning. For this attack to have any effect, the resolver under attack must have set `synth-from-dnssec yes;` (which is the default).
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.
Related
Weakness · CWE (1)
- CWE-1284 Improper Validation of Specified Quantity in Input weakness
References
- https://downloads.isc.org/isc/bind9/9.20.26 downloads.isc.org
- https://downloads.isc.org/isc/bind9/9.21.24 downloads.isc.org
- https://kb.isc.org/docs/cve-2026-11721 kb.isc.org