Use-after-free in Linux kernel - CVE-2026-89545

Vulnerability identifier: #VU149264

CSH Severity: Low

CVSS v4: 0 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-89545

CWE-ID: CWE-416

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to trigger a use-after-free.

The vulnerability exists due to improper RCU synchronization in the SunRPC service request cleanup routine when RCU readers traverse the thread list after a service request is removed. A local user can cause RCU readers to dereference freed request argument memory to trigger a use-after-free.

The issue affects request data accessed by readers such as nfsd_nl_rpc_status_get_dumpit().

Linux kernel
Debian Linux
openEuler
Ubuntu
linux-nvidia-tegra (Ubuntu package)
linux (Ubuntu package)
linux-aws (Ubuntu package)
linux-gcp (Ubuntu package)
linux-oracle (Ubuntu package)
linux-ibm (Ubuntu package)
linux-hwe-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
kernel
python3-perf-debuginfo
python3-perf
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-source
kernel-headers
kernel-devel
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
bpftool
linux (Debian package)

Install security update from vendor's repository.

linux-nvidia-tegra (Ubuntu package) - update to 6.8.0-1038.42
linux (Ubuntu package) - update to 7.0.0-42.42
linux-aws (Ubuntu package) - update to 7.0.0-1016.17
linux-gcp (Ubuntu package) - update to 7.0.0-1016.18
linux-oracle (Ubuntu package) - update to 7.0.0-1015.16
linux-ibm (Ubuntu package) - update to 7.0.0-1017.17
linux-hwe-7.0 (Ubuntu package) - update to 7.0.0-42.42~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1017.17
kernel - update to 5.10.0-339.0.0.240
python3-perf-debuginfo - update to 5.10.0-339.0.0.240
python3-perf - update to 5.10.0-339.0.0.240
perf-debuginfo - update to 5.10.0-339.0.0.240
perf - update to 5.10.0-339.0.0.240
kernel-tools-devel - update to 5.10.0-339.0.0.240
kernel-tools-debuginfo - update to 5.10.0-339.0.0.240
kernel-tools - update to 5.10.0-339.0.0.240
kernel-source - update to 5.10.0-339.0.0.240
kernel-headers - update to 5.10.0-339.0.0.240
kernel-devel - update to 5.10.0-339.0.0.240
kernel-debugsource - update to 5.10.0-339.0.0.240
kernel-debuginfo - update to 5.10.0-339.0.0.240
bpftool-debuginfo - update to 5.10.0-339.0.0.240
bpftool - update to 5.10.0-339.0.0.240
linux (Debian package) - update to 6.12.111-1

• https://git.kernel.org/stable/c/08bc49e0541260bf294962cf889a32a2d2713ad6
• https://git.kernel.org/stable/c/c479bde671cbe2f9e152834a8b0eb7c3c295bbaf
• https://git.kernel.org/stable/c/e0c5693d3f9a5d4911735ab0e0eba4eecb1f1090

• Use-after-free in Linux kernel sunrpc
• Debian update for linux
• openEuler 22.03 LTS SP4 update for kernel
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more
• Ubuntu update for linux-nvidia-tegra