#VU103029 NULL pointer dereference in Linux kernel - CVE-2025-21642

Vulnerability identifier: #VU103029

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-2025-21642

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 mptcp_pernet_set_defaults(), mptcp_set_scheduler() and proc_scheduler() functions in net/mptcp/ctrl.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/6035702381c35a8f16757332381e58b348a9eaf9
https://git.kernel.org/stable/c/c0e394fd6b887e84da17e38aaa6c1c104f9c86c2
https://git.kernel.org/stable/c/d38e26e36206ae3d544d496513212ae931d1da0a

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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.