#VU106119 Improper locking in Linux kernel - CVE-2025-21886

Vulnerability identifier: #VU106119

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-2025-21886

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 destroy_unused_implicit_child_mr() function in drivers/infiniband/hw/mlx5/odp.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/3d8c6f26893d55fab218ad086719de1fc9bb86ba
https://git.kernel.org/stable/c/a095ede2daca49d15e74d66d014883f2fa8bb924
https://git.kernel.org/stable/c/cb96ae783e7249e8e5a50c22952c0bb2983133df

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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.