RHSA-2025:23414 - Security Advisory

Topic

An update for bind is now available for Red Hat Enterprise Linux 6 Extended Lifecycle Support - EXTENSION.

Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

The Berkeley Internet Name Domain (BIND) is an implementation of the Domain Name System (DNS) protocols. BIND includes a DNS server (named); a resolver library (routines for applications to use when interfacing with DNS); and tools for verifying that the DNS server is operating correctly.

Security Fix(es):

• bind: DNS forwarders - cache poisoning vulnerability (CVE-2021-25220)
• bind: Cache poisoning attacks with unsolicited RRs (CVE-2025-40778)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux Server 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension (for IBM z Systems) 6 s390x

Fixes

• BZ - 2064512 - CVE-2021-25220 bind: DNS forwarders - cache poisoning vulnerability
• BZ - 2405827 - CVE-2025-40778 bind: Cache poisoning attacks with unsolicited RRs

CVEs

• CVE-2021-25220
• CVE-2025-40778

References

• https://access.redhat.com/security/updates/classification/#important