#VU104979 Out-of-bounds read in Linux kernel - CVE-2025-21743

Vulnerability identifier: #VU104979

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-2025-21743

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 ipheth_rcvbulk_callback_ncm() function in drivers/net/usb/ipheth.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/18bf6f5cce3172cb303c3f0551aa9443d5ed74f8
https://git.kernel.org/stable/c/c219427ed296f94bb4b91d08626776dc7719ee27
https://git.kernel.org/stable/c/d677e7dd59ad6837496f5a02d8e5d39824278dfd
https://git.kernel.org/stable/c/d824a964185910e317287f034c0a439c08b4fe49

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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.