RHSA-2026:3110 - Security Advisory

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: page_pool: Fix use-after-free in page_pool_recycle_in_ring (CVE-2025-38129)
• kernel: Linux kernel:A use-after-free in bridge multicast in br_multicast_port_ctx_init (CVE-2025-38248)
• kernel: smc: Fix use-after-free in __pnet_find_base_ndev() (CVE-2025-40064)
• kernel: mlxsw: spectrum_mr: Fix use-after-free when updating multicast route stats (CVE-2025-68800)
• kernel: Linux kernel: Use-after-free in teql queueing discipline can lead to privilege escalation (CVE-2026-23074)

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 Real Time 8 x86_64
• Red Hat Enterprise Linux for Real Time for NFV 8 x86_64

Fixes

• BZ - 2376034 - CVE-2025-38129 kernel: page_pool: Fix use-after-free in page_pool_recycle_in_ring
• BZ - 2378981 - CVE-2025-38248 kernel: Linux kernel:A use-after-free in bridge multicast in br_multicast_port_ctx_init
• BZ - 2406747 - CVE-2025-40064 kernel: smc: Fix use-after-free in __pnet_find_base_ndev()
• BZ - 2429065 - CVE-2025-68800 kernel: mlxsw: spectrum_mr: Fix use-after-free when updating multicast route stats
• BZ - 2436791 - CVE-2026-23074 kernel: Linux kernel: Use-after-free in teql queueing discipline can lead to privilege escalation

CVEs

• CVE-2025-38129
• CVE-2025-38248
• CVE-2025-40064
• CVE-2025-68800
• CVE-2026-23074

References

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