#VU104963 Use-after-free in Linux kernel - CVE-2025-21718

Vulnerability identifier: #VU104963

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-2025-21718

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 rose_heartbeat_expiry(), rose_timer_expiry() and rose_idletimer_expiry() functions in net/rose/rose_timer.c. A local user can escalate privileges on the system.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 6.1 - 6.1.128

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External links
https://git.kernel.org/stable/c/1992fb261c90e9827cf5dc3115d89bb0853252c9
https://git.kernel.org/stable/c/51c128ba038cf1b79d605cbee325919b45ab95a5
https://git.kernel.org/stable/c/58051a284ac18a3bb815aac6289a679903ddcc3f
https://git.kernel.org/stable/c/5de7665e0a0746b5ad7943554b34db8f8614a196
https://git.kernel.org/stable/c/f55c88e3ca5939a6a8a329024aed8f3d98eea8e4
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.1.129

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Q & A

Can this vulnerability be exploited remotely?

Is there known malware, which exploits this vulnerability?