#VU105668 Improper locking in Linux kernel - CVE-2025-21851

Vulnerability identifier: #VU105668

Vulnerability 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-2025-21851

CWE-ID: CWE-667

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor: Linux Foundation

Description

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

The vulnerability exists due to improper locking within the kernel/bpf/arena.c. A local user can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: All versions

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External links
https://git.kernel.org/stable/c/517e8a7835e8cfb398a0aeb0133de50e31cae32b
https://git.kernel.org/stable/c/787d556a3de447e70964a4bdeba9196f62a62b1e
https://git.kernel.org/stable/c/c1f3f3892d4526f18aaeffdb6068ce861e793ee3

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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.