Beacon Object Files

1. ETW Patching
2. API Function Utility
3. Syscalls Shellcode Injection

ETW Patching BOF

Simple Beacon object file to patch (and revert) the EtwEventWrite function in ntdll.dll to degrade ETW based logging.

All credit goes to @xpn: https://www.mdsec.co.uk/2020/03/hiding-your-net-etw/.

API Function Utility BOF

Beacon object file to:

• Read bytes of loaded module API function
• Read relevant on-disk DLL and compare functions to identify differencies (e.g. EPP/EDR hooking)
• Patch functions with the on-disk copy (i.e. API unhooking)

Credit goes to @spottheplanet for the Dll parsing technique: https://www.ired.team/offensive-security/defense-evasion/retrieving-ntdll-syscall-stubs-at-run-time

Syscalls Shellcode Injection BOF (64-bit only)

Beacon object file to:

• Fetch Syscall Stubs from on-disk ntdll.dll (All credit to @odzhan - https://github.com/odzhan/injection/blob/master/syscalls/inject_dll.c)
• Inject shellcode (either custom or beacon) into remote process using NtOpenProcess -> NtAllocateVirtualMemory -> NtWriteVirtualMemory -> NtCreateThreadEx.

Credit also to @tomcarver16 for their DLL inject BOF and aggressor script (https://github.com/tomcarver16/BOF-DLL-Inject)