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Vulnerability · CVE-2025-38539

In the Linux kernel, the following vulnerability has been resolved: tracing: Add down_write(trace_event_sem) when adding trace event When a module is loaded, it adds t…

Published Aug 16, 2025 · corrected/updated Oct 15, 2026 · linux linux kernel · evidence confidence high

In the Linux kernel, the following vulnerability has been resolved: tracing: Add down_write(trace_event_sem) when adding trace event When a module is loaded, it adds trace events defined by the module. It may also need to modify the modules trace printk formats to replace enum names with their values. If two modules are loaded at the same time, the adding of the event to the ftrace_events list can corrupt the walking of the list in the code that is modifying the printk format strings and crash the kernel. The addition of the event should take the trace_event_sem for write while it adds the new event. Also add a lockdep_assert_held() on that semaphore in __trace_add_event_dirs() as it iterates the list.

Grounded briefings

Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.

Executive

CVE-2025-38539 is a medium public vulnerability record for linux linux kernel. It is not currently listed in the CISA Known Exploited catalog. Check the linked vendor or CERT advisories for patch status. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.

System administrator

Identify whether linux linux kernel is in your estate, then compare installed versions with the affected ranges. Affected packages or ranges on record: debian/debian linux (11.0); linux/linux kernel; linux/linux kernel (6.16). Check the linked vendor or CERT advisories for patch status. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.

Security analyst

Signals on file: CVSS 5.5, EPSS 0.2%. It is not currently listed in the CISA Known Exploited catalog. Sources contributing to this record: cve_org, epss, nvd. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.

Exploitation and remediation

  • Exploitation evidence

    Not listed as known exploited in CISA KEV. Not in CISA KEV or VulnCheck KEV.

  • Patch and remediation

    No required-action text is stored yet. Use the vendor or CERT links in Sources for patch availability.

  • Safe detection guidance

    Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Aug 16, 2025 · NIST NVD

    Detected

    In the Linux kernel, the following vulnerability has been resolved: tracing: Add down_write(trace_event_sem) when adding trace event When a module is loaded, it adds trace events defined by the module. It may also need to modify the modules trace printk formats to replace enum names with their values. If two modules are loaded at the same time, the adding of the event to the ftrace_events list can

  2. Oct 15, 2026 · NIST NVD

    Updated

    In the Linux kernel, the following vulnerability has been resolved: tracing: Add down_write(trace_event_sem) when adding trace event When a module is loaded, it adds trace events defined by the module. It may also need to modify the modules trace printk formats to replace enum names with their values. If two modules are loaded at the same time, the adding of the event to the ftrace_events list can

Affected

  • cpe debian/debian linux11.0
  • cpe linux/linux kernelversion unspecified
  • cpe linux/linux kernel6.16

Sources

  • CVE.orgVulnerability recordCVE-2025-38539

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2025-38539

    30-day exploitation probability 0.2%

    first.org
  • NIST NVDVulnerability recordCVE-2025-38539

    In the Linux kernel, the following vulnerability has been resolved: tracing: Add down_write(trace_event_sem) when adding trace event When a module is loaded, it adds trace events defined by the module. It may also need to modify the modules trace printk formats to replace enum

    nvd.nist.gov

References