#VU105010 NULL pointer dereference in Linux kernel - CVE-2025-21720

Vulnerability identifier: #VU105010

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-2025-21720

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 include/net/xfrm.h. A local user can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 6.6 - 6.6.75

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External links
https://git.kernel.org/stable/c/600258d555f0710b9c47fb78d2d80a4aecd608cc
https://git.kernel.org/stable/c/6945701ca1572f81bc9bb46f624b02eabb3eaf3e
https://git.kernel.org/stable/c/981ad4c882096e7375b8c2181dd4c3ee58ea5bae
https://git.kernel.org/stable/c/c6e1b2cac24b2a4d1dd472071021bf00c26450eb
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.6.76

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Q & A

Can this vulnerability be exploited remotely?

Is there known malware, which exploits this vulnerability?