#VU104995 NULL pointer dereference in Linux kernel - CVE-2025-21776

Vulnerability identifier: #VU104995

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-2025-21776

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 hub_probe() function in drivers/usb/core/hub.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/2240fed37afbcdb5e8b627bc7ad986891100e05d
https://git.kernel.org/stable/c/5b9778e1fe715700993ce436c152dc3b7df0b490
https://git.kernel.org/stable/c/62d8f4c5454dd39aded4f343720d1c5a1803cfef
https://git.kernel.org/stable/c/c3720b04df84b5459050ae4e03ec7d545652f897
https://git.kernel.org/stable/c/e905a0fca7bff0855d312c16f71e60e1773b393e

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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.