RHSA-2023:4255 - Security Advisory

Topic

An update for kernel-rt is now available for Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support, Red Hat Enterprise Linux 8.4 Telecommunications Update Service, and Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions.

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: tcindex: use-after-free vulnerability in traffic control index filter allows privilege escalation (CVE-2023-1281)
• 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):

• kernel-rt: update RT source tree to the latest RHEL-8.4z18 Batch (BZ#2209986)

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 x86_64 - Extended Update Support Extension 8.4 x86_64
• 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 - 2181847 - CVE-2023-1281 kernel: tcindex: use-after-free vulnerability in traffic control index filter allows privilege escalation
• BZ - 2196105 - CVE-2023-32233 kernel: netfilter: use-after-free in nf_tables when processing batch requests can lead to privilege escalation

CVEs

• CVE-2023-1281
• CVE-2023-32233

References

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