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In Windows 11, Microsoft introduced a new clipboard monitoring mechanism via `WtdProcessString()` in wtdccm.dll. This function triggers when:
– Clipboard data format is CF_TEXT/CF_UNICODETEXT
– Text length is between 7–257 characters
– `WNF_WTD_SENSOR_MONITORING_STATE` is enabled (network-dependent)
The function performs an RPC call to `SFRClipboardInput` in `sfapm.dll` via LPC port \RPC Control\clipsfk, potentially inspecting URLs or sensitive data.
You Should Know:
1. Disable WTD Monitoring
:: Rename wtdccm.dll to prevent loading takeown /f C:\Windows\System32\wtdccm.dll icacls C:\Windows\System32\wtdccm.dll /grant Administrators:F ren C:\Windows\System32\wtdccm.dll wtdccm.dll.bak
2. Check WNF State via PowerShell
Query WNF_WTD_SENSOR_MONITORING_STATE (requires admin)
Get-WinEvent -LogName "Microsoft-Windows-Kernel-WNF/Operational" |
Where-Object { $_.Id -eq 0x1F4 } |
Format-List -Property Message
3. Debugging Workaround for LSASS Deadlock
.sympath srvhttps://msdl.microsoft.com/download/symbols !load ntdll !wnf state WNF_WTD_SENSOR_MONITORING_STATE
4. Network Dependency Verification
:: Check if WTD depends on TCPIP/BFE (Base Filtering Engine) sc query wtd.sys fltmc volumes | findstr "wtd"
5. Reverse Engineering sfapm.dll
Use Ghidra/IDA to analyze `SFRClipboardInput`:
strings -el sfapm.dll | grep -i "clipboard|password|http"
References:
What Undercode Say
Microsoft’s opaque clipboard monitoring raises privacy/security concerns. The LSASS debugger deadlock highlights poor isolation. Sysadmins should audit `wtdccm.dll` and `sfapm.dll` via Process Monitor. For developers, hooking `WtdProcessString()` via Detours may bypass inspections. Future Windows updates may expand this to credential theft detection.
Expected Output:
1. wtdccm.dll renamed → Clipboard monitoring disabled 2. WNF state logged → "SensorMonitoringEnabled: 1" 3. LSASS debugger → Avoids RPC deadlock
Prediction
Microsoft will integrate this into “Secured-Core” PCs for real-time credential phishing protection, but may face backlash over opaque data collection.
IT/Security Reporter URL:
Reported By: Alex S – Hackers Feeds
Extra Hub: Undercode MoN
Basic Verification: Pass ✅
