CVE-2026-5946

HIGH

BIND 9.11.0-9.16.50, 9.18.0-9.18.48, 9.20.0-9.20.22, 9.21.0-9.21.21 - DoS via Non-IN DNS Message Handling

Title source: llm
STIX 2.1

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.

References (4)

Core 4

Scores

CVSS v3 7.5
EPSS 0.0004
EPSS Percentile 11.0%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-125 CWE-20 CWE-617 CWE-754 CWE-843
Status published
Products (8)
isc/bind 9.11.0 - 9.16.50
ISC/BIND 9 9.11.0 - 9.16.50
ISC/BIND 9 9.11.3-S1 - 9.16.50-S1
ISC/BIND 9 9.18.0 - 9.18.48
ISC/BIND 9 9.18.11-S1 - 9.18.48-S1
ISC/BIND 9 9.20.0 - 9.20.22
ISC/BIND 9 9.20.9-S1 - 9.20.22-S1
ISC/BIND 9 9.21.0 - 9.21.21
Published May 20, 2026
Tracked Since May 20, 2026