dbcve.org
Windows 10 1507Operating system · Microsoft

CVE-2025-49675

HIGH · 7.8 CVSS v3.1 Published 2025-07-08
Fix available
A fix is available. Upgrade to 10.0.10240.21073 / 10.0.14393.8246 or later.
See remediation →
80/100
Remediation priority · High
Zero-click

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 · unedited
Use after free in Kernel Streaming WOW Thunk Service Driver allows an authorized attacker to elevate privileges locally.

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 confidence

A use-after-free vulnerability exists in the Kernel Streaming WOW Thunk Service Driver, a Windows kernel component handling 32-bit application compatibility. An authorized local attacker can exploit this memory corruption issue to elevate privileges to kernel/system level, potentially executing arbitrary code with full system access.

MitigationApply Microsoft security updates for the affected Windows versions once available. Prioritize patching endpoint systems given the local attack vector and high impact of privilege escalation.

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 data
Windows 10 1507Operating system
Affected:< 10.0.10240.21073
Windows 10 1607Operating system
Affected:< 10.0.14393.8246
Windows 10 1809Operating system
Affected:< 10.0.17763.7558
Windows 10 21h2Operating system
Affected:< 10.0.19044.6093
Windows 10 22h2Operating system
Affected:< 10.0.19045.6093
Windows 11 22h2Operating system
Affected:< 10.0.22621.5624
Windows 11 23h2Operating system
Affected:< 10.0.22631.5624
Windows 11 24h2Operating system
Affected:< 10.0.26100.4652

CVSS 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 checks

Work through these to decide whether this CVE applies to you.

  1. Check Windows build version
    Run 'winver' from the Run dialog or execute 'systeminfo | findstr /C:"Build"' in Command Prompt to obtain the OS build number
    Affected if The build number is below 10.0.10240.21073 (Windows 10 1507), 10.0.14393.8246 (Windows 10 1607), 10.0.17763.7558 (Windows 10 1809), 10.0.19044.6093 (Windows 10 21h2), 10.0.19045.6093 (Windows 10 22h2), 10.0.22621.5624 (Windows 11 22h2), 10.0.22631.5624 (Windows 11 23h2), or 10.0.26100.4652 (Windows
  2. Verify kswhdmthk.sys driver presence
    Check for the presence of kswdmthk.sys (Kernel Streaming WOW Thunk Service Driver) in the System32\drivers folder using 'dir C:\Windows\System32\drivers\kswdmthk.sys' or by enumerating driver files
    Affected if The kswdmthk.sys driver file exists on the system, indicating the vulnerable component is installed (this driver is present by default in affected Windows versions)
  3. Confirm driver file version if accessible
    Right-click kswdmthk.sys, select Properties, then view the Details tab to see File Version, or run 'powershell (Get-Item C:\Windows\System32\drivers\kswdmthk.sys).VersionInfo'
    Affected if The driver version is not available or is older than the version bundled with the patched builds listed above

The system is affected if it runs any Windows 10 or 11 version with a build number lower than the security update thresholds for its respective release, and the kswdmthk.sys driver is present (which is the default state in vulnerable versions).

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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.

dbcve · scoped
Upgrade available Upgrade to 10.0.10240.21073 / 10.0.14393.8246 / 10.0.17763.7558 or later
Fixed in 10.0.10240.2107310.0.14393.824610.0.17763.7558
Interim mitigation

Apply Microsoft security updates for the affected Windows versions once available. Prioritize patching endpoint systems given the local attack vector and high impact of privilege escalation.

Recommended fix High confidence

Windows 10 1507: 10.0.10240.21073+ | Windows 10 1607: 10.0.14393.8246+ | Windows 10 1809: 10.0.17763.7558+ | Windows 10 21h2: 10.0.19044.6093+ | Windows 10 22h2: 10.0.19045.6093+ | Windows 11 22h2: 10.0.22621.5624+ | Windows 11 23h2: 10.0.22631.5624+ | Windows 11 24h2: 10.0.26100.4652+

  1. Identify the current Windows build version by running 'winver' or 'systeminfo | findstr /B /C:"OS Version"'
  2. Determine which Windows 10 or Windows 11 version and build you are running
  3. Navigate to Windows Update Settings > Check for Updates
  4. Alternatively, manually download the specific security update from the Microsoft Update Catalog for your Windows version
  5. Install the cumulative security update for the respective month (refer to MSRC for the specific KB article)
  6. Restart the system to complete the patch installation
  7. Verify the installation by checking that the build number matches or exceeds the fixed version for your Windows release

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Windows 10 1507 Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing8.0 h
  • Review / QA4.0 h
18.0 hours of engineering $3,040
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Scan for this in your stack

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dbcve dependency scanner

Check whether your project pulls in CVE-2025-49675 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-49675 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • 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
  • No spam, self-promotion, credentials, or personal data