CVE WatchSep 8, 2026

CVE-2025-38352

Linux Kernel Time-of-Check Time-of-Use (TOCTOU) Race Condition Vulnerability

CVSS

7.8

High

EPSS

1.3%

p71

KEV

YES

Sep 4, 2025

Exploit Today

0-100

Published: Jul 22, 2025 · Last modified: Sep 8, 2026 · CWE-367

EPSS · 30d

1.3%EPSS · 30 days1.3%

2026-09-162026-10-14

KEV catalog record

Product

Linux / Kernel

Vulnerability

Linux Kernel Time-of-Check Time-of-Use (TOCTOU) Race Condition Vulnerability

Added to KEV

Sep 4, 2025

Remediate by

Sep 25, 2025

Known ransomware use

Summary description

Linux kernel contains a time-of-check time-of-use (TOCTOU) race condition vulnerability that has a high impact on confidentiality, integrity, and availability.

Required action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Notes

This vulnerability affects a common open-source component, third-party library, or a protocol used by different products. Please check with specific vendors for information on patching status. For more information, please see: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=2c72fe18cc5f9f1750f5bc148cf1c94c29e106ff ; https://source.android.com/docs/security/bulletin/2025-09-01 ; https://nvd.nist.gov/vuln/detail/CVE-2025-38352

Technical 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.

Official references

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