Use-after-free in Linux kernel - CVE-2026-72427
Published: August 15, 2026
Vulnerability identifier: #VU143014
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-72427
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a use-after-free in the cgroup BPF effective program array handling in kernel/bpf/cgroup.c when updating or detaching BPF programs with BPF_F_PREORDER configurations. A local user can trigger incorrect effective array slot selection to cause a denial of service.
The issue occurs because preorder programs are placed at the front of the effective array, so linear traversal of the program list can select the wrong slot.
Affected software
Linux kernel
Ubuntu
linux-gcp-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
Ubuntu
linux-gcp-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
How to mitigate CVE-2026-72427
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3
linux-gcp-7.0 (Ubuntu package) - addressed in versions 7.0.0-38.38~24.04.4, 7.0.0-1013.13~24.04.1, 7.0.0-1014.14~24.04.1
linux-azure-7.0 (Ubuntu package) - addressed in versions 7.0.0-1016.16~24.04.1, 7.0.0-1017.17~24.04.1
linux-gcp-7.0 (Ubuntu package) - addressed in versions 7.0.0-38.38~24.04.4, 7.0.0-1013.13~24.04.1, 7.0.0-1014.14~24.04.1
linux-azure-7.0 (Ubuntu package) - addressed in versions 7.0.0-1016.16~24.04.1, 7.0.0-1017.17~24.04.1
External References
- https://git.kernel.org/stable/c/41b4320b84fdafe1ab586b06453d30d50415db59
- https://git.kernel.org/stable/c/525e408c27ae714e538b8c608c3a974df3ab6c92
- https://git.kernel.org/stable/c/9697db03e010391c55ae75192cbdf30c5a72c114
- https://git.kernel.org/stable/c/b584f107ab90222bd825dcb4c5977326ff684109
- https://git.kernel.org/stable/c/f08aaee3152d0dfc578b3f2586932d82062701dd