#VU106871 Input validation error in Linux kernel - CVE-2025-21903

Vulnerability identifier: #VU106871

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-2025-21903

CWE-ID: CWE-20

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 improper input validation within the mctp_i3c_header_create() function in drivers/net/mctp/mctp-i3c.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 - 6.12.18

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External links
https://git.kernel.org/stable/c/740bf9c9b715cc327d34b1e2d4ee79fcd4c47a56
https://git.kernel.org/stable/c/cf7ee25e70c6edfac4553d6b671e8b19db1d9573
https://git.kernel.org/stable/c/d8be54c35aee29d96d1350b1b6f153be4da37c07
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.12.19

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Q & A

Can this vulnerability be exploited remotely?

Is there known malware, which exploits this vulnerability?