RHSA-2021:4875: Important: kernel-rt security and bug fix update

Published Nov 30, 2021
·
Updated

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)

Affected Software

15 affected componentsFixes available
redhat/kernel-rt<4.18.0-193.70.1.rt13.120.el8_2
4.18.0-193.70.1.rt13.120.el8_2
redhat/kernel-rt<4.18.0-193.70.1.rt13.120.el8_2
4.18.0-193.70.1.rt13.120.el8_2
redhat/kernel-rt-core<4.18.0-193.70.1.rt13.120.el8_2
4.18.0-193.70.1.rt13.120.el8_2
redhat/kernel-rt-debug<4.18.0-193.70.1.rt13.120.el8_2
4.18.0-193.70.1.rt13.120.el8_2
redhat/kernel-rt-debug-core<4.18.0-193.70.1.rt13.120.el8_2
4.18.0-193.70.1.rt13.120.el8_2
redhat/kernel-rt-debug-debuginfo<4.18.0-193.70.1.rt13.120.el8_2
4.18.0-193.70.1.rt13.120.el8_2
redhat/kernel-rt-debug-devel<4.18.0-193.70.1.rt13.120.el8_2
4.18.0-193.70.1.rt13.120.el8_2
redhat/kernel-rt-debug-modules<4.18.0-193.70.1.rt13.120.el8_2
4.18.0-193.70.1.rt13.120.el8_2
redhat/kernel-rt-debug-modules-extra<4.18.0-193.70.1.rt13.120.el8_2
4.18.0-193.70.1.rt13.120.el8_2
redhat/kernel-rt-debuginfo<4.18.0-193.70.1.rt13.120.el8_2
4.18.0-193.70.1.rt13.120.el8_2
redhat/kernel-rt-devel<4.18.0-193.70.1.rt13.120.el8_2
4.18.0-193.70.1.rt13.120.el8_2
redhat/kernel-rt-modules<4.18.0-193.70.1.rt13.120.el8_2
4.18.0-193.70.1.rt13.120.el8_2
redhat/kernel-rt-modules-extra<4.18.0-193.70.1.rt13.120.el8_2
4.18.0-193.70.1.rt13.120.el8_2
redhat/kernel-rt-debug-kvm<4.18.0-193.70.1.rt13.120.el8_2
4.18.0-193.70.1.rt13.120.el8_2
redhat/kernel-rt-kvm<4.18.0-193.70.1.rt13.120.el8_2
4.18.0-193.70.1.rt13.120.el8_2

Remediation

Event History

Nov 30, 2021
Advisory Published
via Red Hat·12:00 AM

Frequently Asked Questions

1

What is the severity of RHSA-2021:4875?

The severity of RHSA-2021:4875 is classified as important.

2

How do I fix RHSA-2021:4875?

To fix RHSA-2021:4875, update the kernel-rt packages to version 4.18.0-193.70.1.rt13.120.el8_2.

3

What vulnerabilities are addressed in RHSA-2021:4875?

RHSA-2021:4875 addresses a use-after-free vulnerability in drivers/infiniband/core/ucma.c (CVE-2020-36385).

4

Which packages are affected by RHSA-2021:4875?

The affected packages include kernel-rt and its variants such as kernel-rt-core, kernel-rt-debug, and kernel-rt-modules.

5

Is a reboot required after applying the fix for RHSA-2021:4875?

Yes, a reboot is required after updating the kernel-rt packages to ensure the changes take effect.

Contact

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