RHSA-2026:59994: Important: kernel security update

Q: Which environments are covered by this advisory?

The advisory lists Red Hat Enterprise Linux for x86_64 Extended Life Cycle Long Life and Red Hat Enterprise Linux Server AUS. It covers the kernel and related packages including kernel-core, bpftool, bpftool-debuginfo, kernel-abi-stablelists, and kernel-cross-headers.

Q: What component and vulnerability class are involved?

The issue is a use-after-free vulnerability in the Linux kernel IPv6 networking code. It involves fib6_rule_suppress and a stale res->rt6 pointer.

Published Aug 26, 2026

Updated

Important: kernel security update

Other sources

The kernel packages contain the Linux kernel, the core of any Linux operating system.Security Fix(es): kernel: net: ipv6: use-after-free in fib6rulesuppress due to stale res->rt6 pointer (CVE-2026-74581) 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.

— Red Hat

Affected Software

28 affected componentsFixes available

Red Hat Red Hat Enterprise Linux for x86_64 - Extended Life Cycle Long Life

Red Hat Red Hat Enterprise Linux Server - AUS

redhat/kernel<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/bpftool<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/bpftool-debuginfo<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel-abi-stablelists<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel-core<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel-cross-headers<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel-debug<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel-debug-core<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel-debug-debuginfo<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel-debug-devel<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel-debug-modules<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel-debug-modules-extra<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel-debuginfo<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel-devel<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel-doc<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel-headers<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel-modules<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel-modules-extra<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel-tools<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel-tools-debuginfo<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/kernel-tools-libs<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/perf<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/perf-debuginfo<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/python3-perf<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

redhat/python3-perf-debuginfo<4.18.0-305.202.1.el8_4

4.18.0-305.202.1.el8_4

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade redhat/kernel to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/bpftool to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/bpftool-debuginfo to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/kernel-abi-stablelists to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/kernel-core to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/kernel-cross-headers to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/kernel-debug to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/kernel-debug-core to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/kernel-debug-debuginfo to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/kernel-debug-devel to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/kernel-debug-modules to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/kernel-debug-modules-extra to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/kernel-debuginfo to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/kernel-devel to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/kernel-doc to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/kernel-headers to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/kernel-modules to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/kernel-modules-extra to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/kernel-tools to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/kernel-tools-debuginfo to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/kernel-tools-libs to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/perf to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/perf-debuginfo to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/python3-perf to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade redhat/python3-perf-debuginfo to a version that resolves this vulnerability.
Fixed in 4.18.0-305.202.1.el8_4
Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Patch CVE-2026-74581
Operational
Reboot the system to ensure the kernel security update takes effect.

Event History

Aug 26, 2026

Advisory Published

via Red Hat·12:00 AM

Data Sourced

via Red Hat·12:00 AM

RemedyDescriptionAffected Software

Advisory Published

via Red Hat·07:00 AM

Data Sourced

via Red Hat·07:00 AM

Severity

Frequently Asked Questions

Which environments are covered by this advisory?

The advisory lists Red Hat Enterprise Linux for x86_64 Extended Life Cycle Long Life and Red Hat Enterprise Linux Server AUS. It covers the kernel and related packages including kernel-core, bpftool, bpftool-debuginfo, kernel-abi-stablelists, and kernel-cross-headers.

What component and vulnerability class are involved?

The issue is a use-after-free vulnerability in the Linux kernel IPv6 networking code. It involves fib6_rule_suppress and a stale res->rt6 pointer.

What should be prioritized when applying the update?

Prioritize systems running affected Red Hat kernel packages where IPv6 networking functionality is in use. The advisory classifies the update as Important and rates the issue high severity.

RHSA-2026:59994: Important: kernel security update

Other sources

Affected Software

Remediation

Event History

Frequently Asked Questions

Which environments are covered by this advisory?

What component and vulnerability class are involved?

What should be prioritized when applying the update?

Company

Resources

Contact

Frequently Asked Questions

Which environments are covered by this advisory?

What component and vulnerability class are involved?

What should be prioritized when applying the update?