#VU105141 NULL pointer dereference in Linux kernel - CVE-2025-21814

Vulnerability identifier: #VU105141

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-2025-21814

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 ptp_getcycles64() and ptp_clock_register() functions in drivers/ptp/ptp_clock.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/5d1041c76de656f9f8d5a192218039a9acf9bd00
https://git.kernel.org/stable/c/755caf4ee1c615ee5717862e427124370f46b1f3
https://git.kernel.org/stable/c/81846070cba17125a866e8023c01d3465b153339
https://git.kernel.org/stable/c/8441aea46445252df5d2eed6deb6d5246fc24002
https://git.kernel.org/stable/c/fd53aa40e65f518453115b6f56183b0c201db26b

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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.