#VU103024 NULL pointer dereference in Linux kernel - CVE-2025-21637

Vulnerability identifier: #VU103024

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-2025-21637

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 proc_sctp_do_auth() function in net/sctp/sysctl.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/55627918febdf9d71107a1e68d1528dc591c9a15
https://git.kernel.org/stable/c/5b77d73f3be5102720fb685b9e6900e3500e1096
https://git.kernel.org/stable/c/c10377bbc1972d858eaf0ab366a311b39f8ef1b6
https://git.kernel.org/stable/c/e919197fb8616331f5dc81e4c3cc3d12769cb725

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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.