RHSA-2026:45116 - 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: KVM: x86: Don't (re)check L1 intercepts when completing userspace I/O (CVE-2025-40026)
• kernel: xfrm single-frag length not properly limited
• kernel: dm log: fix out-of-bounds write due to region_count overflow (CVE-2026-53059)
• kernel: tipc: fix double-free in tipc_buf_append() (CVE-2026-52993)

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

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 x86_64 - Extended Life Cycle 8.10 x86_64

Fixes

• BZ - 2406712 - CVE-2025-40026 kernel: KVM: x86: Don't (re)check L1 intercepts when completing userspace I/O
• BZ - 2492277 - CVE-2026-53059 kernel: dm log: fix out-of-bounds write due to region_count overflow
• BZ - 2492437 - CVE-2026-52993 kernel: tipc: fix double-free in tipc_buf_append()

CVEs

• CVE-2025-40026
• CVE-2026-52993
• CVE-2026-53059
• CVE-2026-64561

References

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