DNS Message Handling Vulnerabilities in BIND by ISC
CVE-2026-5946

7.5HIGH

Key Information:

Vendor

Isc
Status
Bind 9
Vendor
CVE Published:
20 May 2026

Badges

👾 Exploit Exists

What is CVE-2026-5946?

Several vulnerabilities have been detected in the named component of BIND related to the processing of DNS messages that are outside the Internet (IN) class, such as CHAOS and HESIOD, as well as those indicating meta-classes like ANY or NONE. These vulnerabilities may lead to assertion failures in various contexts including recursion, dynamic updates, zone change notifications, or when processing IN-specific record types using non-IN data. Users of affected versions should consider immediate remediation to mitigate risk.

Affected Version(s)

BIND 9 9.11.0 <= 9.16.50

BIND 9 9.18.0 <= 9.18.48

BIND 9 9.20.0 <= 9.20.22

References

https://kb.isc.org/docs/cve-2026-5946
vendor-advisory
https://downloads.isc.org/isc/bind9/9.18.49
patch
https://downloads.isc.org/isc/bind9/9.20.23
patch

CVSS V3.1

Score:
7.5
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

ISC would like to thank Mcsky23 for bringing this vulnerability to our attention.
.