CVE-2025-38352: Linux Kernel Time-of-Check Time-of-Use (TOCTOU) Race Condition Vulnerability

Reference page built from the source records below, each shown as its source publishes it. Dataset version ref-a7324cfcc0e1, updated 2026-11-02T23:39:54.475Z.

CISA Known Exploited Vulnerabilities

Name
Linux Kernel Time-of-Check Time-of-Use (TOCTOU) Race Condition Vulnerability
Vendor
Linux
Product
Kernel
Added to the catalog
2025-09-04
Due date for US federal agencies
2025-09-25
Weaknesses
CWE-367
Catalog version
2026.10.30

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 (CISA)

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

Ransomware use: CISA does not mark known use of this vulnerability in ransomware campaigns.

Links in CISA's notes

Read on 2026-11-02T23:39:54.475Z under licence cisa-kev-cc0@b0067899 from https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json

NVD analysis

Status
Analyzed
Published
2025-07-22T08:15:23.577
Last modified
2026-09-08T18:17:32.447
Weaknesses
CWE-367

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.

MetricScoreSeverityVectorScored by
CVSS 3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary)

References

This product uses the NVD API but is not endorsed or certified by the NVD.

Read on 2026-11-02T23:42:22.836Z under licence nvd-api-terms-of-use@ff2a5288 from https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2025-38352

CVE record

Title (CNA)
posix-cpu-timers: fix race between handle_posix_cpu_timers() and posix_cpu_timer_del()
Assigner
Linux
State
PUBLISHED
Published
2025-07-22T08:04:25.277Z
Updated
2026-09-08T15:32:28.302Z

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.

References

Read on 2026-11-03T02:16:22.334Z under licence cve-terms-of-use@81bfa2f3 from https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2025/38xxx/CVE-2025-38352.json

Defensive techniques (MITRE D3FEND)

D3FEND maps these defensive techniques to the weakness (CWE) that NVD lists for this CVE, through the digital artifacts the weakness affects. D3FEND does not say they stop this vulnerability.

CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition

D3FEND ontology version 1.6.0.

Read on 2026-11-02T23:56:13.751Z under licence d3fend-terms-of-use@f98cbc7e from https://d3fend.mitre.org/api/weakness/cwe/CWE-367.json

MITRE D3FEND™ knowledge graph. © 2025 The MITRE Corporation.
"The MITRE Corporation (MITRE) hereby grants you a non-exclusive, royalty-free license to use D3FEND for research, development, and commercial purposes. Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." Terms: https://d3fend.mitre.org/tou/

Sources and licences

  • CISA

    Source: CISA Catalog of Known Exploited Vulnerabilities, version 2026.10.30, CC0 1.0. Use of this data does not imply endorsement by CISA or DHS.

    CC0 1.0 Universal

  • National Vulnerability Database (NIST)

    This product uses the NVD API but is not endorsed or certified by the NVD.

    NVD API Terms of Use (NIST publications in the public domain, 17 U.S.C. 105)

  • CVE Program, The MITRE Corporation

    Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation. CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy.

    CVE Program Terms of Use ("CVE Usage" licence)

  • MITRE D3FEND

    MITRE D3FEND™ knowledge graph. © 2025 The MITRE Corporation.
    "The MITRE Corporation (MITRE) hereby grants you a non-exclusive, royalty-free license to use D3FEND for research, development, and commercial purposes. Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." Terms: https://d3fend.mitre.org/tou/

    MITRE D3FEND Terms of Use (site + knowledge graph); source repo MIT

Cite this page

Dragons Eye Ransomware Tracker, "CVE-2025-38352: Linux Kernel Time-of-Check Time-of-Use (TOCTOU) Race Condition Vulnerability",
entity page, dataset version ref-a7324cfcc0e1, updated 2026-11-02T23:39:54.475Z,
https://ransomware-tracker.com/cve/CVE-2025-38352 (accessed 2026-11-03).
Underlying source: CISA Catalog of Known Exploited Vulnerabilities, version 2026.10.30.
Underlying source: National Vulnerability Database (NIST), CVE API 2.0, record last modified 2026-09-08T18:17:32.447.
Underlying source: CVE List (CVE Program, The MITRE Corporation), record updated 2026-09-08T15:32:28.302Z.
Underlying source: MITRE D3FEND, ontology version 1.6.0.

Pages change. The dataset version identifies the data, but no archive of old versions is kept, so this citation cannot be replayed later.

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