#VU103013 Use-after-free in Linux kernel - CVE-2025-21652

Vulnerability identifier: #VU103013

Vulnerability risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2025-21652

CWE-ID: CWE-416

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 a use-after-free error within the default_operstate() function in net/core/link_watch.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/52a24538d569f48e79d1a169a5d359d384152950
https://git.kernel.org/stable/c/ba9f7c16ec879c83bb4f80406773a911aace8267
https://git.kernel.org/stable/c/cb358ff94154774d031159b018adf45e17673941

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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.