- Issued:
- 2026-06-10
- Updated:
- 2026-06-10
RHSA-2026:25120 - Critical: kernel-rt security update
Synopsis
Critical: kernel-rt security update
Type/Severity
Security Advisory Critical
Topic
An update for kernel-rt is now available for Red Hat Enterprise Linux 8.
Red Hat Product Security has rated this update as having a security impact of Critical. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
Description
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.
Solution
For details on how to apply this update, which includes the changes described in this advisory, refer to:
https://access.redhat.com/articles/11258
The system must be rebooted for this update to take effect.
Affected Products
| Product | Version | Arch |
|---|---|---|
| Red Hat Enterprise Linux for x86_64 - Extended Life Cycle | 8.10 | x86_64 |
| Red Hat Enterprise Linux for Real Time | 8 | x86_64 |
| Red Hat Enterprise Linux for Real Time for NFV | 8 | x86_64 |
Updated Packages
- kernel-rt-kvm-4.18.0-553.132.1.rt7.473.el8_10.x86_64.rpm
- kernel-rt-devel-4.18.0-553.132.1.rt7.473.el8_10.x86_64.rpm
- kernel-rt-debug-modules-extra-4.18.0-553.132.1.rt7.473.el8_10.x86_64.rpm
- kernel-rt-debuginfo-common-x86_64-4.18.0-553.132.1.rt7.473.el8_10.x86_64.rpm
- kernel-rt-debug-debuginfo-4.18.0-553.132.1.rt7.473.el8_10.x86_64.rpm
- kernel-rt-modules-extra-4.18.0-553.132.1.rt7.473.el8_10.x86_64.rpm
- kernel-rt-debug-devel-4.18.0-553.132.1.rt7.473.el8_10.x86_64.rpm
- kernel-rt-debug-kvm-4.18.0-553.132.1.rt7.473.el8_10.x86_64.rpm
- kernel-rt-debug-core-4.18.0-553.132.1.rt7.473.el8_10.x86_64.rpm
- kernel-rt-debug-modules-4.18.0-553.132.1.rt7.473.el8_10.x86_64.rpm
- kernel-rt-4.18.0-553.132.1.rt7.473.el8_10.x86_64.rpm
- kernel-rt-core-4.18.0-553.132.1.rt7.473.el8_10.x86_64.rpm
- kernel-rt-debug-4.18.0-553.132.1.rt7.473.el8_10.x86_64.rpm
- kernel-rt-4.18.0-553.132.1.rt7.473.el8_10.src.rpm
- kernel-rt-modules-4.18.0-553.132.1.rt7.473.el8_10.x86_64.rpm
- kernel-rt-debuginfo-4.18.0-553.132.1.rt7.473.el8_10.x86_64.rpm
Fixes
- This content is not included.BZ - 2351619
- This content is not included.BZ - 2420279
- This content is not included.BZ - 2424881
- This content is not included.BZ - 2432389
- This content is not included.BZ - 2432400
- This content is not included.BZ - 2451218
- This content is not included.BZ - 2461471
- This content is not included.BZ - 2461480
- This content is not included.BZ - 2464351
- This content is not included.BZ - 2464397
- This content is not included.BZ - 2467234
- This content is not included.BZ - 2482166
- This content is not included.BZ - 2482532
CVEs
- 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
References
Additional information
- The Red Hat security contact is This content is not included.secalert@redhat.com. More contact details at Security Contacts and Procedures.
- Offline Security Data data is available for integration with other systems. See Offline Security Data API to get started.