CVE-2026-5946
HIGH EPSS 57.3%
Published May 20, 20261mo ago · Modified Jun 17, 20262w ago
7.5 CVSS 3.1
Published May 20, 2026 1mo ago
Last Modified Jun 17, 2026 2w ago
Description
Multiple flaws have been identified in `named` related to the handling of DNS messages whose CLASS is not Internet (`IN`) — for example, `CHAOS` or `HESIOD`, or DNS messages that specify meta-classes (`ANY` or `NONE`) in the question section. Specially crafted requests reaching the affected code paths — recursion, dynamic updates (`UPDATE`), zone change notifications (`NOTIFY`), or processing of `IN`-specific record types in non-`IN` data — can cause assertion failures in `named`. This issue affects BIND 9 versions 9.11.0 through 9.16.50, 9.18.0 through 9.18.48, 9.20.0 through 9.20.22, 9.21.0 through 9.21.21, 9.11.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.48-S1, and 9.20.9-S1 through 9.20.22-S1.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High
Threat Intelligence
EPSS Exploit Probability
57.3% percentile
Exploit & Patch Status
No Known Exploit
Patch Available
Weaknesses 5
CWE-125 Out-of-bounds Read Memory Safety
CWE-20 Improper Input Validation Validation
CWE-617
CWE-754
CWE-843
Affected Products 4
References 4
- downloads.isc.org https://downloads.isc.org/isc/bind9/9.18.49
- downloads.isc.org https://downloads.isc.org/isc/bind9/9.20.23
- downloads.isc.org https://downloads.isc.org/isc/bind9/9.21.22
- kb.isc.org https://kb.isc.org/docs/cve-2026-5946
Remediation
- downloads.isc.org https://downloads.isc.org/isc/bind9/9.18.49
- downloads.isc.org https://downloads.isc.org/isc/bind9/9.20.23
- downloads.isc.org https://downloads.isc.org/isc/bind9/9.21.22