#VU104961 Use-after-free in Linux kernel - CVE-2025-21726

Vulnerability identifier: #VU104961

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-2025-21726

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 padata_reorder() and invoke_padata_reorder() functions in kernel/padata.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/6f45ef616775b0ce7889b0f6077fc8d681ab30bc
https://git.kernel.org/stable/c/7000507bb0d2ceb545c0a690e0c707c897d102c2
https://git.kernel.org/stable/c/8ca38d0ca8c3d30dd18d311f1a7ec5cb56972cac
https://git.kernel.org/stable/c/a54091c24220a4cd847d5b4f36d678edacddbaf0
https://git.kernel.org/stable/c/dd7d37ccf6b11f3d95e797ebe4e9e886d0332600

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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.