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Michael Bateman recently reviewed the BOF Development and Tradecraft course by Zero-Point Security, highlighting its value for red teamers and offensive security professionals. If you’re considering enrolling, check out the full review here: Red Team Training Reviews. To learn more about the course, visit: Zero-Point Security.
You Should Know: Essential BOF Development Commands and Techniques
1. Compiling BOFs with GCC/MinGW:
x86_64-w64-mingw32-gcc -o payload.o -c payload.c -masm=intel
2. Extracting Shellcode from Object Files:
objdump -d payload.o | grep -Po '\s\K[a-f0-9]{2}(?=\s)' | sed 's/^/\x/g' | perl -pe 's/\r?\n//' | sed 's/$/\n/'
3. Debugging BOFs with WinDbg:
!load winext/mex !mex.dph -a <BOF_address>
4. Common COFF (BOF) Loader in C2 Frameworks:
BOOL LoadBOF(LPCSTR bofPath, LPVOID bofMemory) {
HANDLE hFile = CreateFileA(bofPath, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, 0, NULL);
DWORD bofSize = GetFileSize(hFile, NULL);
bofMemory = VirtualAlloc(NULL, bofSize, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
ReadFile(hFile, bofMemory, bofSize, NULL, NULL);
CloseHandle(hFile);
return TRUE;
}
5. Testing BOFs in Cobalt Strike:
./agscript [CS_IP] [PORT] [USER] [PASSWORD] /path/to/bof_script.cna
6. Avoiding Detection with Obfuscation:
msfvenom -p windows/x64/exec CMD="calc.exe" -f raw | xor.py -k 0x41 -o obfuscated.bin
7. Using Syscalls Directly in BOFs (Windows):
mov r10, rcx mov eax, [syscall_number] syscall ret
What Undercode Say
BOF (Buffer Overflow) development remains a critical skill for red teamers, enabling custom payload execution while evading EDR solutions. Mastering COFF loading, syscall techniques, and debugging in WinDbg enhances tradecraft. For hands-on practice, always test in isolated environments and study Windows API internals (e.g., ntdll.dll).
Expected Output:
- Compiled BOF (
payload.o) - Shellcode string (
\x41\x42...) - Successful execution in Cobalt Strike/CScript
- Obfuscated payload (
obfuscated.bin)
References:
Reported By: Alex Reid – Hackers Feeds
Extra Hub: Undercode MoN
Basic Verification: Pass ✅
