REDHAT-BUG-2503721: High severity Internet Systems Consortium BIND 9 vulnerability

Published Jul 21, 2026
·
Updated

An attacker who knows (or guesses) that a resolver uses RPZ with wildcard CNAME policies can craft query names long enough to trigger a NAMETOOLONG error condition during RPZ processing. This is not handled correctly and may lead to defeating the RPZ rule. It also may lead to an unexpected exit of the BIND 9 software.

Affected Software

1 affected component
Internet Systems Consortium BIND 9

Event History

Jul 21, 2026
Data Sourced
via Red Hat·04:27 PM
DescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of REDHAT-BUG-2503721?

The severity of REDHAT-BUG-2503721 is classified as high with a score of 7.

2

How do I fix REDHAT-BUG-2503721?

To fix REDHAT-BUG-2503721, update the Internet Systems Consortium BIND 9 to the latest version that addresses this vulnerability.

3

What are the potential impacts of REDHAT-BUG-2503721?

The potential impacts of REDHAT-BUG-2503721 include the possibility of defeating RPZ rules and causing unexpected exits during DNS query processing.

4

Who is affected by REDHAT-BUG-2503721?

Users of Internet Systems Consortium BIND 9 that utilize RPZ with wildcard CNAME policies are affected by REDHAT-BUG-2503721.

5

Is there a workaround for REDHAT-BUG-2503721?

Currently, the recommended action for REDHAT-BUG-2503721 is to apply the available patches, as no specific workaround is suggested.

Contact

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