Improper locking in Linux kernel cgroup

1) Improper locking

EUVDB-ID: #VU103035

Risk: Low

CVSSv4.0: 4.3 [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/E:U/U:Clear]

CVE-ID: CVE-2025-21634

CWE-ID: CWE-667 - Improper Locking

Exploit availability: No

Description

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to improper locking within the cpuset_write_resmask() function in kernel/cgroup/cpuset.c. A local user can perform a denial of service (DoS) attack.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Linux kernel: 6.12 - 6.12.9

CPE2.3

• cpe:2.3:o:linux_foundation:linux_kernel:6.12:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:6.12.1:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:6.12.2:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:6.12.3:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:6.12.4:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:6.12.5:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:6.12.6:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:6.12.7:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:6.12.8:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:6.12.9:*:*:*:*:*:*:*

External links

https://git.kernel.org/stable/c/11cb1d643a74665a4e14749414f48f82cbc15c64
https://git.kernel.org/stable/c/3cb97a927fffe443e1e7e8eddbfebfdb062e86ed
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.12.10
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.13

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.