RHSA-2023:5794 - 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: net/sched: cls_u32 component reference counter leak if tcf_change_indev() fails (CVE-2023-3609)
• kernel: net/sched: cls_fw component can be exploited as result of failure in tcf_change_indev function (CVE-2023-3776)
• kernel: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and cls_route (CVE-2023-4128)
• kernel: save/restore speculative MSRs during S3 suspend/resume (CVE-2023-1637)

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

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 - 2181891 - CVE-2023-1637 kernel: save/restore speculative MSRs during S3 suspend/resume
• BZ - 2225097 - CVE-2023-3776 kernel: net/sched: cls_fw component can be exploited as result of failure in tcf_change_indev function
• BZ - 2225201 - CVE-2023-3609 kernel: net/sched: cls_u32 component reference counter leak if tcf_change_indev() fails
• BZ - 2225511 - CVE-2023-4128 kernel: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and cls_route

CVEs

• CVE-2023-1637
• CVE-2023-3609
• CVE-2023-3776
• CVE-2023-4128

References

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