UAC bypass detection, Children of Eventvwr.exe, CompMgmtLauncher, Fodhelper


BLUF:
As Countercept noted, Look for children of:
    Eventvwr.exe CompMgmtLauncher.exe Fodhelper.exe

A quicky on some old UAC bypasses since it just came up again ITW.

SBousseaden shared an Anyrun and some notes on two UAC bypasses:

mscfile\shell\open\command
ms-settings\shell\open\command

mscfile activates from eventvwr.exe or CompMgmtLauncher.exe
ms-settings activates using Fodhelper.exe

They are well documented. Eventvwr has been patched but CompMgmtLauncher still works, fodhelper, I couldn't test but I assume it works the same way.

Testing for the regmods are fine using an EDR but a quick and dirty method is to look for children of the three processes and filter the normal ones.



References:
https://twitter.com/SBousseaden/status/1143848669407588352

https://twitter.com/countercept/status/842023313467707393

https://github.com/ChaitanyaHaritash/My-Exploits/tree/master/COMPMGMTLAUNCHER_UAC_BYPASS

https://enigma0x3.net/2016/08/15/fileless-uac-bypass-using-eventvwr-exe-and-registry-hijacking/

https://pentestlab.blog/2017/06/07/uac-bypass-fodhelper/

https://winscripting.blog/2017/05/12/first-entry-welcome-and-uac-bypass/

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