#VU104975 Out-of-bounds read in Linux kernel - CVE-2025-21734

Vulnerability identifier: #VU104975

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-2025-21734

CWE-ID: CWE-125

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 an out-of-bounds read error within the fastrpc_get_args() function in drivers/misc/fastrpc.c. A local user can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 6.1 - 6.1.128, 6.6 - 6.6.77, 6.12 - 6.12.13, 6.13 - 6.13.2

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External links
https://git.kernel.org/stable/c/24a79c6bc8de763f7c50f4f84f8b0c183bc25a51
https://git.kernel.org/stable/c/c0464bad0e85fcd5d47e4297d1e410097c979e55
https://git.kernel.org/stable/c/c3f7161123fcbdc64e90119ccce292d8b66281c4
https://git.kernel.org/stable/c/c56ba3ea8e3c9a69a992aad18f7a65e43e51d623
https://git.kernel.org/stable/c/e966eae72762ecfdbdb82627e2cda48845b9dd66
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.1.129
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.12.14
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.13.3
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.14
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.6.78

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Q & A

Can this vulnerability be exploited remotely?

Is there known malware, which exploits this vulnerability?