#VU103919 NULL pointer dereference in Linux kernel - CVE-2025-21695

Vulnerability identifier: #VU103919

Vulnerability risk: Low

CVSSv4.0: 1.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:U/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2025-21695

CWE-ID: CWE-476

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 NULL pointer dereference within the dell_uart_bl_serdev_probe() function in drivers/platform/x86/dell/dell-uart-backlight.c. A local user can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 6.12, 6.12.1, 6.12.2, 6.12.3, 6.12.4, 6.12.5, 6.12.6, 6.12.7, 6.12.8, 6.12.9, 6.12.10

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External links
https://git.kernel.org/stable/c/1b2128aa2d45ab20b22548dcf4b48906298ca7fd
https://git.kernel.org/stable/c/d3a24d923333f75aaece9acb051d676edc0afb75
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.12.11

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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.