#VU104139 Buffer overflow in Linux kernel - CVE-2025-21704

Vulnerability identifier: #VU104139

Vulnerability risk: Low

CVSSv4.0: 4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:U/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2025-21704

CWE-ID: CWE-119

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 escalate privileges on the system.

The vulnerability exists due to memory corruption within the acm_process_notification() and acm_ctrl_irq() functions in drivers/usb/class/cdc-acm.c. A local user can escalate privileges on the system.

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/383d516a0ebc8641372b521c8cb717f0f1834831
https://git.kernel.org/stable/c/6abb510251e75f875797d8983a830e6731fa281c
https://git.kernel.org/stable/c/7828e9363ac4d23b02419bf2a45b9f1d9fb35646
https://git.kernel.org/stable/c/e563b01208f4d1f609bcab13333b6c0e24ce6a01
https://git.kernel.org/stable/c/f64079bef6a8a7823358c3f352ea29a617844636

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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.