Obfuscation / Packing × ESET NOD32 Antivirus

bypassed ESET NOD32 antivirus by modifying the Meterpreter DLL source and recompiling, and by embedding encoded shellcode

The attack evaded NOD32 by: 1) Recompiling the metsrv.x86.dll from source with debug build to change its signature, preventing detection when loaded reflectively. 2) Generating shikata_ga_nai-encoded Meterpreter shellcode, embedding it in a C++ executable, and adding a runtime check that only executes the payload if the executable filename matches a specific string, avoiding static analysis detection.

Monitor for suspicious process creation with unusual command-line arguments or filenames that match known penetration testing tools. Use behavior-based detection to identify Meterpreter-like network connections and in-memory DLL loading patterns. Ensure AV signatures are updated and consider application whitelisting to prevent execution of unauthorized binaries.