RHEL 8 : kernel-rt (RHSA-2026:25120)

high Nessus Plugin ID 320512

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-2026:25120 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: geneve: Fix use-after-free in geneve_find_dev(). (CVE-2025-21858)

* kernel: smc: Fix use-after-free in tcp_write_timer_handler() (CVE-2023-53781)

* kernel: nbd: defer config unlock in nbd_genl_connect (CVE-2025-68366)

* kernel: libceph: prevent potential out-of-bounds reads in handle_auth_done() (CVE-2026-22984)

* kernel: libceph: replace overzealous BUG_ON in osdmap_apply_incremental() (CVE-2026-22990)

* kernel: netfilter: nf_tables: release flowtable after rcu grace period on error (CVE-2026-23392)

* kernel: ALSA: 6fire: fix use-after-free on disconnect (CVE-2026-31581)

* kernel: smb: client: fix OOB reads parsing symlink error response (CVE-2026-31613)

* kernel: ip6_tunnel: clear skb2->cb[] in ip4ip6_err() (CVE-2026-43037)

* kernel: ipv6: icmp: clear skb2->cb[] in ip6_err_gen_icmpv6_unreach() (CVE-2026-43038)

* kernel: dlm: validate length in dlm_search_rsb_tree (CVE-2026-43125)

* kernel: RDMA/rxe: Fix double free in rxe_srq_from_init (CVE-2026-45852)

* kernel: RDMA/mlx4: Fix mis-use of RCU in mlx4_srq_event() (CVE-2026-46181)

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-2026:25120.

See Also

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

https://bugzilla.redhat.com/show_bug.cgi?id=2351619

https://bugzilla.redhat.com/show_bug.cgi?id=2420279

https://bugzilla.redhat.com/show_bug.cgi?id=2424881

https://bugzilla.redhat.com/show_bug.cgi?id=2432389

https://bugzilla.redhat.com/show_bug.cgi?id=2432400

https://bugzilla.redhat.com/show_bug.cgi?id=2451218

https://bugzilla.redhat.com/show_bug.cgi?id=2461471

https://bugzilla.redhat.com/show_bug.cgi?id=2461480

https://bugzilla.redhat.com/show_bug.cgi?id=2464351

https://bugzilla.redhat.com/show_bug.cgi?id=2464397

https://bugzilla.redhat.com/show_bug.cgi?id=2467234

https://bugzilla.redhat.com/show_bug.cgi?id=2482166

https://bugzilla.redhat.com/show_bug.cgi?id=2482532

http://www.nessus.org/u?864d98e4

https://access.redhat.com/errata/RHSA-2026:25120

Plugin Details

Severity: High

ID: 320512

File Name: redhat-RHSA-2026-25120.nasl

Version: 1.1

Type: Local

Agent: unix

Published: 6/11/2026

Updated: 6/11/2026

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

Risk Information

VPR

Risk Factor: High

Score: 7.4

Vendor

Vendor Severity: Critical

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-2026-31581

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-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, p-cpe:/a:redhat:enterprise_linux:kernel-rt

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: 6/10/2026

Vulnerability Publication Date: 4/9/2024

Reference Information

CVE: CVE-2023-53781, CVE-2025-21858, CVE-2025-68366, CVE-2026-22984, CVE-2026-22990, CVE-2026-23392, CVE-2026-31581, CVE-2026-31613, CVE-2026-43037, CVE-2026-43038, CVE-2026-43125, CVE-2026-45852, CVE-2026-46181

CWE: 125, 130, 366, 416, 617, 825, 843, 911

RHSA: 2026:25120