RHEL 8 : kernel-rt (RHSA-2026:6036)

high Nessus Plugin ID 304304

Synopsis

The remote Red Hat host is missing one or more security updates for kernel-rt.

Description

The remote Redhat Enterprise Linux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2026:6036 advisory.

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: Linux kernel: Use-After-Free vulnerability in ATM subsystem (CVE-2025-38180)

* kernel: macvlan: fix error recovery in macvlan_common_newlink() (CVE-2026-23209)

* kernel: net/sched: cls_u32: use skb_header_pointer_careful() (CVE-2026-23204)

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.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Update the RHEL kernel-rt package based on the guidance in RHSA-2026:6036.

See Also

https://access.redhat.com/security/updates/classification/#moderate

https://bugzilla.redhat.com/show_bug.cgi?id=2376376

https://bugzilla.redhat.com/show_bug.cgi?id=2439900

https://bugzilla.redhat.com/show_bug.cgi?id=2439931

http://www.nessus.org/u?47cecb72

https://access.redhat.com/errata/RHSA-2026:6036

Plugin Details

Severity: High

ID: 304304

File Name: redhat-RHSA-2026-6036.nasl

Version: 1.1

Type: local

Agent: unix

Published: 3/30/2026

Updated: 3/30/2026

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Continuous Assessment, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

Vendor

Vendor Severity: Moderate

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5

Vector: CVSS2#AV:L/AC:L/Au:S/C:C/I:C/A:C

CVSS Score Source: CVE-2026-23209

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:redhat:enterprise_linux:kernel-rt, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-core, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-devel, p-cpe:/a:redhat:enterprise_linux:kernel-rt-devel, p-cpe:/a:redhat:enterprise_linux:kernel-rt-kvm, p-cpe:/a:redhat:enterprise_linux:kernel-rt-core, p-cpe:/a:redhat:enterprise_linux:kernel-rt-modules, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-modules-extra, p-cpe:/a:redhat:enterprise_linux:kernel-rt-modules-extra, cpe:/o:redhat:rhel_eus:8.10, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-kvm, cpe:/o:redhat:enterprise_linux:8, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-modules

Required KB Items: Host/local_checks_enabled, Host/RedHat/release, Host/RedHat/rpm-list, Host/cpu

Exploit Ease: No known exploits are available

Patch Publication Date: 3/30/2026

Vulnerability Publication Date: 7/4/2025

Reference Information

CVE: CVE-2025-38180, CVE-2026-23204, CVE-2026-23209

CWE: 1285, 825, 911

RHSA: 2026:6036