#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: All versions

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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

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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.