Important: kernel-rt security and bug fix update

Topic

An update for kernel-rt is now available for Red Hat Enterprise Linux 9.0 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: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and cls_route (CVE-2023-4128)
• kernel: nf_tables: use-after-free in nft_chain_lookup_byid() (CVE-2023-31248)
• kernel: nf_tables: stack-out-of-bounds-read in nft_byteorder_eval() (CVE-2023-35001)
• kernel: cls_flower: out-of-bounds write in fl_set_geneve_opt() (CVE-2023-35788)
• kernel: hash collisions in the IPv6 connection lookup table (CVE-2023-1206)
• kernel: Spectre v2 SMT mitigations problem (CVE-2023-1998)
• kernel: fbcon: shift-out-of-bounds in fbcon_set_font() (CVE-2023-3161)
• kernel: denial of service problem in net/unix/diag.c (CVE-2023-28327)

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-9.0.z12 Batch (BZ#2232645)

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 for x86_64 - 4 years of updates 9.0 x86_64
• Red Hat Enterprise Linux for Real Time for NFV for x86_64 - 4 years of updates 9.0 x86_64

Fixes

• BZ - 2175903 - CVE-2023-1206 kernel: hash collisions in the IPv6 connection lookup table
• BZ - 2177382 - CVE-2023-28327 kernel: denial of service problem in net/unix/diag.c
• BZ - 2187257 - CVE-2023-1998 kernel: Spectre v2 SMT mitigations problem
• BZ - 2213485 - CVE-2023-3161 kernel: fbcon: shift-out-of-bounds in fbcon_set_font()
• BZ - 2215768 - CVE-2023-35788 kernel: cls_flower: out-of-bounds write in fl_set_geneve_opt()
• BZ - 2220892 - CVE-2023-35001 kernel: nf_tables: stack-out-of-bounds-read in nft_byteorder_eval()
• BZ - 2220893 - CVE-2023-31248 kernel: nf_tables: use-after-free in nft_chain_lookup_byid()
• 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-2023-1206
• CVE-2023-1998
• CVE-2023-3161
• CVE-2023-4128
• CVE-2023-28327
• CVE-2023-31248
• CVE-2023-35001
• CVE-2023-35788

References

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