#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, 6.12.1, 6.12.2, 6.12.3, 6.12.4, 6.12.5, 6.12.6, 6.12.7, 6.12.8, 6.12.9, 6.12.10, 6.12.11, 6.12.12, 6.12.13

---

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

---

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.