CVE-2025-38352

CVE-2025-38352 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 7.4. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2025-09-04). The underlying weakness is classified as CWE-367.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: posix-cpu-timers: fix race between handle_posix_cpu_timers() and posix_cpu_timer_del() If an exiting non-autoreaping task has already passed exit_notify() and calls handle_posix_cpu_timers() from IRQ, it can be reaped by its parent or debugger right after unlock_task_sighand(). If a concurrent posix_cpu_timer_del() runs at that moment, it won't be able to detect timer->it.cpu.firing != 0: cpu_timer_task_rcu() and/or lock_task_sighand() will fail. Add the tsk->exit_state check into run_posix_cpu_timers() to fix this. This fix is not needed if CONFIG_POSIX_CPU_TIMERS_TASK_WORK=y, because exit_task_work() is called before exit_notify(). But the check still makes sense, task_work_add(&tsk->posix_cputimers_work.work) will fail anyway in this case.

Frequently asked questions

What is CVE-2025-38352?
In the Linux kernel, the following vulnerability has been resolved: posix-cpu-timers: fix race between handle_posix_cpu_timers() and posix_cpu_timer_del() If an exiting non-autoreaping task has already passed exit_notify() and calls handle_posix_cpu_timers() from IRQ, it can be reaped by its parent or debugger right after unlock_task_sighand(). If a concurrent posix_cpu_timer_del() runs at that moment, it won't be able to detect timer->it.cpu.firing != 0: cpu_timer_task_rcu() and/or lock_task_sighand() will fail. Add the tsk->exit_state check into run_posix_cpu_timers() to fix this. This fix is not needed if CONFIG_POSIX_CPU_TIMERS_TASK_WORK=y, because exit_task_work() is called before exit_notify(). But the check still makes sense, task_work_add(&tsk->posix_cputimers_work.work) will fail anyway in this case.
How severe is CVE-2025-38352?
CVE-2025-38352 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over local access with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-38352 being actively exploited?
Yes. CVE-2025-38352 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2025-09-04, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2025-38352?
CVE-2025-38352 primarily affects Linux Linux Kernel. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-38352?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2025-38352 have an EU (EUVD) identifier?
Yes. CVE-2025-38352 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-22297. It is also flagged as exploited in the EUVD (since 2025-09-04).
When was CVE-2025-38352 published?
CVE-2025-38352 was published on 2025-07-22 and last updated on 2026-06-17.

References

Affected products (3)

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