Internet Shortcut Shell Extension DLL.
rundll32.exe url.dll,OpenURL "C:\test\calc.hta"
Launch a HTML application payload by calling OpenURL.
Invoke an HTML Application via mshta.exe (Default Handler).
c:\windows\system32\url.dll, c:\windows\syswow64\url.dll
Sigma: https://github.com/SigmaHQ/sigma/blob/62d4fd26b05f4d81973e7c8e80d7c1a0c6a29d0e/rules/windows/process_creation/proc_creation_win_rundll32_susp_activity.yml
Adam (OpenURL) (@hexacorn), Jimmy (OpenURL) (@bohops), Malwrologist (FileProtocolHandler - HTA) (@DissectMalware), r0lan (Obfuscation) (@r0lan)