RHSA-2021:5241 — Security Advisory
Red Hat Security Advisory: kernel-rt security and bug fix update
Severity
ModerateRed Hat Product Security
Products
Official CSAF product identity
Published · December 21, 2021
Updated · November 1, 2026
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 Moderate. 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: In Overlayfs missing a check for a negative dentry before calling vfs_rename() (CVE-2021-20321)
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 RHEL-8.5.z1 source tree (BZ#2023988)
-
[rt] RHEL-8.6: disable KASAN, KCSAN and UBSAN for kernel-rt (BZ#2026384)