# CVE-2026-4018: BlackBerry QNX Neutrino Kernel TOCTOU Race Condition in TraceEvent

Source: https://junglewise.ai/threats/cve-2026-4018-blackberry-qnx-neutrino-kernel-toctou-race-condition-in-traceevent  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-14. Updated: 2026-07-14  
License: CC BY 4.0 with a link back

CVE-2026-4018 · Severity: medium · CVSS 6.4 · Published 2026-07-14

A vulnerability exists in the QNX Neutrino kernel, a real-time operating system used in automotive, medical, and industrial systems. An attacker with local access and specific administrative privileges could exploit a timing flaw to crash the system, view sensitive information, or tamper with data. This could lead to service outages or unauthorized modifications in safety-critical environments.

Technologies: [Blackberry QNX OS for Medical](https://junglewise.ai/threats/technologies/qnx-os-for-medical), [Blackberry QNX OS for Safety](https://junglewise.ai/threats/technologies/qnx-os-for-safety), [Blackberry QNX Software Development Platform](https://junglewise.ai/threats/technologies/qnx-software-development-platform). Vendors: [Blackberry](https://junglewise.ai/threats/vendors/blackberry).

## Quick answers

**Is CVE-2026-4018 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-4018 being exploited in the wild.

**How severe is CVE-2026-4018?** Medium severity, with a CVSS score of 6.4, published 14 July 2026.

**Which products and versions are affected?** Blackberry QNX OS for Medical 2.0.2 and earlier; Blackberry QNX OS for Safety 2.0.3 and earlier, 2.1.5 and earlier, 2.2.8 and earlier; Blackberry QNX Software Development Platform 7.0, 7.1.

**Is there a fix for CVE-2026-4018?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-4018 attacked?** It is attacked with local access, in an operating system.

**Am I affected by CVE-2026-4018?** Check whether you run Blackberry QNX OS for Medical, Blackberry QNX OS for Safety or Blackberry QNX Software Development Platform at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A Time-of-Check Time-of-Use (TOCTOU) race condition exists within specific trace commands of the TraceEvent() system call in the QNX Neutrino kernel. To exploit this, an attacker must have local access and possess the PROCMGR_AID_TRACE ability. The vulnerability arises from improper synchronization when handling trace events, allowing a window where data can be modified between its validation and its use. Successful exploitation can result in information disclosure, data tampering, or a kernel-level denial of service (crash). The issue affects QNX Software Development Platform (SDP) versions 7.0 and 7.1, as well as specific versions of QNX OS for Safety and Medical.

## Affected products

- BlackBerry QNX Software Development Platform 7.0, 7.1
- BlackBerry QNX OS for Safety 2.0.3 and earlier, 2.1.5 and earlier, 2.2.8 and earlier
- BlackBerry Ltd. QNX OS for Medical 2.0.2 and earlier

## Timeline

- 2026-07-14: advisory: Advisory published by BlackBerry and NVD

## References

- [https://support.blackberry.com/pkb/s/article/141213](https://support.blackberry.com/pkb/s/article/141213)

## Related threats

- [BlackBerry QNX traceparser improper input validation in decode function](https://junglewise.ai/threats/cve-2026-40272-blackberry-qnx-traceparser-improper-input-validation-in-decode)
- [BlackBerry QNX Neutrino kernel buffer overflow in TraceEvent system call](https://junglewise.ai/threats/cve-2026-4017-blackberry-qnx-neutrino-kernel-buffer-overflow-in-traceevent)
- [BlackBerry QNX Neutrino kernel denial of service in SchedGet](https://junglewise.ai/threats/cve-2026-0515-blackberry-qnx-neutrino-kernel-denial-of-service-in-schedget)