#VU105669 Improper locking in Linux kernel - CVE-2025-21859

Vulnerability identifier: #VU105669

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-2025-21859

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 f_midi_complete() function in drivers/usb/gadget/function/f_midi.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/24a942610ee9bafb2692a456ae850c5b2e409b05
https://git.kernel.org/stable/c/4ab37fcb42832cdd3e9d5e50653285ca84d6686f
https://git.kernel.org/stable/c/8aa6b4be1f4efccbfc533e6ec8841d26e4fa8dba
https://git.kernel.org/stable/c/deeee3adb2c01eedab32c3b4519337689ad02e8a
https://git.kernel.org/stable/c/e9fec6f42c45db2f62dc373fb1a10d2488c04e79

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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.