Important: kernel-rt security and bug fix update

Topic

An update for kernel-rt is now available for Red Hat Enterprise Linux 8.4 Extended Update Support.

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 kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements.

Security Fix(es):

• kernel: new DNS Cache Poisoning Attack based on ICMP fragment needed packets replies (CVE-2021-20322)
• kernel: security regression for CVE-2018-13405 (CVE-2021-4037)
• kernel: buffer overflow in IPsec ESP transformation code (CVE-2022-27666)

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.

Bug Fix(es):

• kernel-rt: update RT source tree to the RHEL-8.4.z9 source tree (BZ#2075148)

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

The system must be rebooted for this update to take effect.

Affected Products

• Red Hat Enterprise Linux for Real Time - Telecommunications Update Service 8.4 x86_64
• Red Hat Enterprise Linux for Real Time for NFV - Telecommunications Update Service 8.4 x86_64

Fixes

• BZ - 2014230 - CVE-2021-20322 kernel: new DNS Cache Poisoning Attack based on ICMP fragment needed packets replies
• BZ - 2027239 - CVE-2021-4037 kernel: security regression for CVE-2018-13405
• BZ - 2061633 - CVE-2022-27666 kernel: buffer overflow in IPsec ESP transformation code

CVEs

• CVE-2021-4037
• CVE-2021-20322
• CVE-2022-27666

References

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