CVE-2026-5946

Name: CVE-2026-5946
Creator: NVD / NIST
Published: 2026-05-20T13:16:40.157+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 0.97%

Last modified Jun 17, 2026

CVE-2026-5946 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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.. EPSS estimates a 0.97% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.97%

57.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Isc	Bind	>= 9.11.0, <= 9.16.50
Isc	Bind	>= 9.18.0, < 9.18.49
Isc	Bind	>= 9.20.0, < 9.20.23
Isc	Bind	>= 9.21.0, < 9.21.22

References

https://downloads.isc.org/isc/bind9/9.18.49Patch
https://downloads.isc.org/isc/bind9/9.20.23Patch
https://downloads.isc.org/isc/bind9/9.21.22Patch
https://kb.isc.org/docs/cve-2026-5946Vendor Advisory

Timeline

Published: May 20, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-5946?

How severe is CVE-2026-5946?

CVE-2026-5946 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.97% probability of exploitation in the next 30 days.

How do I fix CVE-2026-5946?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-5946?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST