slyd0g / LNKMod

C# project to create or modify existing LNKs

LNKMod

Output File Names

• -modify will update the specified .LNK
• -create will create payload.lnk in the current directory unless a custom path is specified using -outputpath

Usage / Test Cases

• Modify (will modify .LNK in current directory, only place one!)
  • Modify path to executable, no arguments
    • .\LNKMod.exe -modify -path "C:\Windows\system32\calc.exe"
  • Modify path to executable and arguments
    • .\LNKMod.exe -modify -path "C:\Windows\system32\cmd.exe" -args "/c notepad.exe"
• Create
  • Create Test.lnk in the parent directory with path to executable, no arguments, and path to icon
    • .\LNKMod.exe -create -outputpath ..\Test.lnk -path "C:\Windows\system32\calc.exe" -icopath "C:\Users\John\AppData\Local\Microsoft\OneDrive\OneDrive.exe"
  • Create payload.lnk in the current directory with path to executable, arguments, and path to icon
    • .\LNKMod.exe -create -path "C:\Windows\system32\cmd.exe" -args "/c calc.exe" -icopath "C:\Users\John\AppData\Local\Microsoft\OneDrive\OneDrive.exe"
  • Sets access/write time to current time and creation time to a (reasonable) random time
• Dump metadata for a specified .LNK
  • .\LNKMod.exe -dump "C:\Users\John\source\repos\LNKMod\LNKMod\bin\Release\payload.lnk"
• Dump metadata for a specified .LNK in JSON format
  • .\LNKMod.exe -dumpjson "C:\Users\John\source\repos\LNKMod\LNKMod\bin\Release\payload.lnk"

Potentially Dangerous Metadata

• CreationTime
• AccessTime
• WriteTime
• DriveSerialNumber
• KnownFolderID (GUID can be converted to a string can leak usernames)
• MachineID (NetBIOS name)

References

• https://github.com/securifybv/ShellLink
• https://github.com/JamesNK/Newtonsoft.Json