Important: kernel-rt security and bug fix update

Topic

An update for kernel-rt is now available for Red Hat Enterprise Linux 8.

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: netfilter: use-after-free in nf_tables when processing batch requests can lead to privilege escalation (CVE-2023-32233)

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):

• smpboot: Scheduler frequency invariance went wobbly, disabling! (BZ#2188316)
• Crash: kernel BUG at kernel/locking/rtmutex.c:1338! (BZ#2188722)
• kernel-rt: update RT source tree to the RHEL-8.8.z0 source tree. (BZ#2196667)

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 8 x86_64
• Red Hat Enterprise Linux for Real Time for NFV 8 x86_64
• Red Hat Enterprise Linux for Real Time - Telecommunications Update Service 8.8 x86_64
• Red Hat Enterprise Linux for Real Time for NFV - Telecommunications Update Service 8.8 x86_64

Fixes

• BZ - 2196105 - CVE-2023-32233 kernel: netfilter: use-after-free in nf_tables when processing batch requests can lead to privilege escalation

CVEs

• CVE-2023-32233

References

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