RHSA-2021:4088: Important: kernel-rt security and bug fix update

Published Nov 2, 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: out-of-bounds write due to a heap buffer overflow in hidinputchangeresolutionmultipliers() of hid-input.c (CVE-2021-0512) kernel: SVM nested virtualization issue in KVM (VMLOAD/VMSAVE) (CVE-2021-3656) 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-8.4.z source tree (BZ#2004117)

Affected Software

15 affected componentsFixes available
redhat/kernel-rt<4.18.0-305.25.1.rt7.97.el8_4
4.18.0-305.25.1.rt7.97.el8_4
redhat/kernel-rt<4.18.0-305.25.1.rt7.97.el8_4
4.18.0-305.25.1.rt7.97.el8_4
redhat/kernel-rt-core<4.18.0-305.25.1.rt7.97.el8_4
4.18.0-305.25.1.rt7.97.el8_4
redhat/kernel-rt-debug<4.18.0-305.25.1.rt7.97.el8_4
4.18.0-305.25.1.rt7.97.el8_4
redhat/kernel-rt-debug-core<4.18.0-305.25.1.rt7.97.el8_4
4.18.0-305.25.1.rt7.97.el8_4
redhat/kernel-rt-debug-debuginfo<4.18.0-305.25.1.rt7.97.el8_4
4.18.0-305.25.1.rt7.97.el8_4
redhat/kernel-rt-debug-devel<4.18.0-305.25.1.rt7.97.el8_4
4.18.0-305.25.1.rt7.97.el8_4
redhat/kernel-rt-debug-modules<4.18.0-305.25.1.rt7.97.el8_4
4.18.0-305.25.1.rt7.97.el8_4
redhat/kernel-rt-debug-modules-extra<4.18.0-305.25.1.rt7.97.el8_4
4.18.0-305.25.1.rt7.97.el8_4
redhat/kernel-rt-debuginfo<4.18.0-305.25.1.rt7.97.el8_4
4.18.0-305.25.1.rt7.97.el8_4
redhat/kernel-rt-devel<4.18.0-305.25.1.rt7.97.el8_4
4.18.0-305.25.1.rt7.97.el8_4
redhat/kernel-rt-modules<4.18.0-305.25.1.rt7.97.el8_4
4.18.0-305.25.1.rt7.97.el8_4
redhat/kernel-rt-modules-extra<4.18.0-305.25.1.rt7.97.el8_4
4.18.0-305.25.1.rt7.97.el8_4
redhat/kernel-rt-debug-kvm<4.18.0-305.25.1.rt7.97.el8_4
4.18.0-305.25.1.rt7.97.el8_4
redhat/kernel-rt-kvm<4.18.0-305.25.1.rt7.97.el8_4
4.18.0-305.25.1.rt7.97.el8_4

Remediation

Event History

Feb 27, 2026
Advisory Published
via Red Hat·03:17 PM
Data Sourced
via Red Hat·03:17 PM
RemedyDescriptionAffected Software
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Frequently Asked Questions

1

What is the severity of RHSA-2021:4088?

The severity of RHSA-2021:4088 is classified as moderate due to a use-after-free vulnerability in the Linux kernel.

2

How do I fix RHSA-2021:4088?

To fix RHSA-2021:4088, you should update your kernel-rt packages to version 4.18.0-305.25.1.rt7.97.el8_4 or later.

3

What is the nature of the vulnerability in RHSA-2021:4088?

The vulnerability in RHSA-2021:4088 is a use-after-free issue in the Infiniband driver, which may allow an attacker to execute arbitrary code.

4

Which packages are affected by RHSA-2021:4088?

The affected packages in RHSA-2021:4088 include kernel-rt, kernel-rt-core, and kernel-rt-debug among others.

5

Is there a specific operating system associated with RHSA-2021:4088?

RHSA-2021:4088 is associated with Red Hat Enterprise Linux 8.

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