#VU105157 Resource management error in Linux kernel - CVE-2025-21816

Vulnerability identifier: #VU105157

Vulnerability risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2025-21816

CWE-ID: CWE-399

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 perform a denial of service (DoS) attack.

The vulnerability exists due to resource management error within the HRTIMER_ACTIVE_SOFT(), DEFINE_PER_CPU(), hrtimer_base_is_online(), lock_hrtimer_base(), raw_spin_unlock(), WRITE_ONCE(), hrtimer_is_hres_enabled() and __hrtimer_start_range_ns() functions in kernel/time/hrtimer.c. A local user can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 6.12 - 6.12.13

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External links
https://git.kernel.org/stable/c/2aecec58e9040ce3d2694707889f9914a2374955
https://git.kernel.org/stable/c/53dac345395c0d2493cbc2f4c85fe38aef5b63f5
https://git.kernel.org/stable/c/e456a88bddae4030ba962447bb84be6669f2a0c1
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.12.14

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Q & A

Can this vulnerability be exploited remotely?

Is there known malware, which exploits this vulnerability?