#VU105670 Improper locking in Linux kernel - CVE-2025-21862

Vulnerability identifier: #VU105670

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-2025-21862

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 init_net_drop_monitor() and exit_net_drop_monitor() functions in net/core/drop_monitor.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/07b598c0e6f06a0f254c88dafb4ad50f8a8c6eea
https://git.kernel.org/stable/c/0efa6c42f81c60d8f72ba7f5ed8d4fec8c526282
https://git.kernel.org/stable/c/219a47d0e6195bd202f22855e35f25bd15bc4d58
https://git.kernel.org/stable/c/b7859e8643e75619b2705b4fcac93ffd94d72b4a
https://git.kernel.org/stable/c/fcfc00bfec7bb6661074cb21356d05a4c9470a3c

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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.