CVE-2025-21436
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedMemory corruption may occur while initiating two IOCTL calls simultaneously to create processes from two different threads.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · moderate confidenceA race condition vulnerability in Windows allows memory corruption when two IOCTL calls to create processes are initiated simultaneously from different threads. The concurrent IOCTL requests to create processes trigger a memory corruption issue, likely due to improper synchronization in the kernel or driver handling process creation.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE dataall versionsall versionsall versionsall versionsall versionsall versionsall versionsall versionsCVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify installed Qualcomm firmware componentsCheck system information or device manager for presence of Qualcomm components such as Fastconnect 7800, QMP1000, SM8735, SM8750, SM8750p, Snapdragon 8 Gen 3, Snapdragon W5+ Gen 1, or SW5100. Run 'wmic bios list full' or check firmware/driver listings.Affected if Any of the listed Qualcomm firmware components are present on the system (all versions are affected).
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Check for the vulnerable process creation IOCTL handlerIdentify the Windows driver that handles process creation IOCTLs. Use tools like 'driverquery' or check registry at HKLM\SYSTEM\CurrentControlSet\Services to list loaded drivers. Look for drivers associated with Qualcomm or process creation functionality.Affected if A driver handling process creation IOCTLs from Qualcomm is loaded on the system.
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Verify concurrent process creation capabilityCheck if the system has any service or application that can trigger the specific IOCTL for process creation. Review any custom or vendor-specific drivers that expose process creation IOCTL interfaces.Affected if The system runs services or drivers that expose process creation IOCTL calls accessible from user mode.
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Monitor for simultaneous process creation eventsUse process monitoring tools (such as Sysmon or Windows Event Logging) to observe if multiple process creation requests occur concurrently. Enable Process Creation auditing and review Event ID 4688 for overlapping timestamps.Affected if The system environment allows or has observed concurrent process creation requests to the same IOCTL handler.
A system is affected if it contains any of the listed Qualcomm firmware components (all versions) and runs a driver that exposes the vulnerable process creation IOCTL interface susceptible to race conditions.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataApply vendor patches from Microsoft or the affected driver vendor as soon as available. In the interim, restrict access to the affected service/driver and monitor for suspicious process creation activity.
- Consultation8.0 h
- Implementation16.0 h
- Testing8.0 h
- Review / QA4.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2025-21436 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2025-21436 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
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