RHSA-2021:2169: Important: kernel-rt security and bug fix update

Published Jun 1, 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: userspace applications can misuse the KVM API to cause a write of 16 bytes at an offset up to 32 GB from vcpu->run (CVE-2021-3501) kernel: nitroenclaves stale file descriptors on failed usercopy (CVE-2021-3543) 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.z0 source tree (BZ#1957489)

Affected Software

15 affected componentsFixes available
redhat/kernel-rt<4.18.0-305.3.1.rt7.75.el8_4
4.18.0-305.3.1.rt7.75.el8_4
redhat/kernel-rt<4.18.0-305.3.1.rt7.75.el8_4
4.18.0-305.3.1.rt7.75.el8_4
redhat/kernel-rt-core<4.18.0-305.3.1.rt7.75.el8_4
4.18.0-305.3.1.rt7.75.el8_4
redhat/kernel-rt-debug<4.18.0-305.3.1.rt7.75.el8_4
4.18.0-305.3.1.rt7.75.el8_4
redhat/kernel-rt-debug-core<4.18.0-305.3.1.rt7.75.el8_4
4.18.0-305.3.1.rt7.75.el8_4
redhat/kernel-rt-debug-debuginfo<4.18.0-305.3.1.rt7.75.el8_4
4.18.0-305.3.1.rt7.75.el8_4
redhat/kernel-rt-debug-devel<4.18.0-305.3.1.rt7.75.el8_4
4.18.0-305.3.1.rt7.75.el8_4
redhat/kernel-rt-debug-modules<4.18.0-305.3.1.rt7.75.el8_4
4.18.0-305.3.1.rt7.75.el8_4
redhat/kernel-rt-debug-modules-extra<4.18.0-305.3.1.rt7.75.el8_4
4.18.0-305.3.1.rt7.75.el8_4
redhat/kernel-rt-debuginfo<4.18.0-305.3.1.rt7.75.el8_4
4.18.0-305.3.1.rt7.75.el8_4
redhat/kernel-rt-devel<4.18.0-305.3.1.rt7.75.el8_4
4.18.0-305.3.1.rt7.75.el8_4
redhat/kernel-rt-modules<4.18.0-305.3.1.rt7.75.el8_4
4.18.0-305.3.1.rt7.75.el8_4
redhat/kernel-rt-modules-extra<4.18.0-305.3.1.rt7.75.el8_4
4.18.0-305.3.1.rt7.75.el8_4
redhat/kernel-rt-debug-kvm<4.18.0-305.3.1.rt7.75.el8_4
4.18.0-305.3.1.rt7.75.el8_4
redhat/kernel-rt-kvm<4.18.0-305.3.1.rt7.75.el8_4
4.18.0-305.3.1.rt7.75.el8_4

Remediation

Event History

Apr 3, 2026
Advisory Published
via Red Hat·03:21 PM
Data Sourced
via Red Hat·03:21 PM
RemedyDescriptionAffected Software
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Frequently Asked Questions

1

What is the severity of RHSA-2021:2169?

The severity of RHSA-2021:2169 is classified as important due to the potential misuse of the KVM API by userspace applications.

2

How do I fix RHSA-2021:2169?

To fix RHSA-2021:2169, update to the kernel-rt package version 4.18.0-305.3.1.rt7.75.el8_4 or later.

3

Which packages are affected by RHSA-2021:2169?

The affected packages include kernel-rt, kernel-rt-core, kernel-rt-debug, and several other kernel-rt related packages.

4

What vulnerabilities does RHSA-2021:2169 address?

RHSA-2021:2169 addresses vulnerabilities that allow userspace applications to misuse the KVM API, leading to unauthorized memory write operations.

5

When was the RHSA-2021:2169 advisory released?

The RHSA-2021:2169 advisory was released on 2021-07-30.

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