#VU111601 Improper locking in Linux kernel - CVE-2025-38040

Vulnerability identifier: #VU111601

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-2025-38040

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 stm32_usart_enable_ms() function in drivers/tty/serial/stm32-usart.c, within the sci_shutdown() function in drivers/tty/serial/sh-sci.c, within the mctrl_gpio_enable_ms() and mctrl_gpio_disable_ms() functions in drivers/tty/serial/serial_mctrl_gpio.c, within the imx_uart_shutdown() function in drivers/tty/serial/imx.c, within the atmel_disable_ms() function in drivers/tty/serial/atmel_serial.c, within the serial8250_disable_ms() function in drivers/tty/serial/8250/8250_port.c. A local user can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's repository.

Vulnerable software versions

Linux kernel: All versions

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External links
https://git.kernel.org/stable/c/1bd2aad57da95f7f2d2bb52f7ad15c0f4993a685
https://git.kernel.org/stable/c/68435c1fa3db696db4f480385db9e50e26691d0d
https://git.kernel.org/stable/c/7187ec6b0b9ff22ebac2c3bb4178b7dbbdc0a55a
https://git.kernel.org/stable/c/c504c11b94d6e4ad818ca5578dffa8ff29ad0f20
https://git.kernel.org/stable/c/e6a46719a2369eb5186d4f7e6c0478720ca1ec3d

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Q & A

Can this vulnerability be exploited remotely?

Is there known malware, which exploits this vulnerability?