RHSA-2021:4875 — Security Advisory
Red Hat Security Advisory: kernel-rt security and bug fix update
Severity
ImportantRed Hat Product Security
Products
Official CSAF product identity
Published · December 1, 2021
Updated · August 7, 2026
Topic
An update for kernel-rt is now available for Red Hat Enterprise Linux 8.2 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: use-after-free in drivers/infiniband/core/ucma.c ctx use-after-free (CVE-2020-36385)
-
kernel: timer tree corruption leads to missing wakeup and system freeze (CVE-2021-20317)
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-8.2.z13 Batch source tree (BZ#2020969)