Use-after-free in Linux kernel - CVE-2026-53129

Vulnerability identifier: #VU135161

CSH Severity: Low

CVSS v4: 6.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-53129

CWE-ID: CWE-416

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local privileged user to cause a denial of service.

The vulnerability exists due to use-after-free in mb_cache_destroy() and mb_cache_shrink_worker() when destroying an mbcache instance while scheduled shrink work is pending or running. A local privileged user can trigger the last put of a mounted ext2, ext4, or ocfs2 filesystem to cause a denial of service.

The issue is only reachable when the attacker can trigger teardown of the cache for a mounted filesystem.

Linux kernel
Anolis OS
Ubuntu
bpftool
python3-perf
perf
kernel-tools-libs-devel
kernel-tools-libs
kernel-tools
kernel-headers
kernel-devel
kernel-debug-devel
kernel-debug
kernel
linux (Ubuntu package)
linux-ibm (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
linux-aws (Ubuntu package)
linux-azure (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
bpftool - update to 6.6.102-7
python3-perf - update to 6.6.102-7
perf - update to 6.6.102-7
kernel-tools-libs-devel - update to 6.6.102-7
kernel-tools-libs - update to 6.6.102-7
kernel-tools - update to 6.6.102-7
kernel-headers - update to 6.6.102-7
kernel-devel - update to 6.6.102-7
kernel-debug-devel - update to 6.6.102-7
kernel-debug - update to 6.6.102-7
kernel - update to 6.6.102-7
linux (Ubuntu package) - addressed in versions 7.0.0-28.28, 7.0.0-28.28.1, 7.0.0-1003.4, 7.0.0-1008.8
linux-ibm (Ubuntu package) - addressed in versions 7.0.0-1008.8, 7.0.0-1010.10
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1009.9
linux-aws (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1015.15
linux-azure (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1010.10

• https://git.kernel.org/stable/c/0e4eff315d799f5842b95872199b0f0fb8ef5f51
• https://git.kernel.org/stable/c/a88d39a74a208e197c03bffaa2df34de732af19f
• https://git.kernel.org/stable/c/b25fd3523bef88fb7ffd4c5b63bbe9c08f73bb4c
• https://git.kernel.org/stable/c/d227786ab1119669df4dc333a61510c52047cce4

• Use-after-free in Linux kernel fs
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux
• Ubuntu update for linux-ibm
• Ubuntu update for linux-azure
• Ubuntu update for linux-aws
• Anolis OS update for kernel:6.6