#VU106111 Use-after-free in Linux kernel - CVE-2025-21888

Vulnerability identifier: #VU106111

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-2025-21888

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 mlx5_free_priv_descs() function in drivers/infiniband/hw/mlx5/mr.c. A local user can escalate privileges on the system.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 6.13 - 6.13.5

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External links
https://git.kernel.org/stable/c/0bd34bdd468e93a779c403de3cf7d43ee633b3e0
https://git.kernel.org/stable/c/abc7b3f1f056d69a8f11d6dceecc0c9549ace770
https://git.kernel.org/stable/c/f1298cad47ae29828c5c5be77e733ccfcaef6a7f
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.13.6

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Q & A

Can this vulnerability be exploited remotely?

Is there known malware, which exploits this vulnerability?