Manual Unpacking Tutorial... | Manual UnPacking (MUP) of NFO v1.0 |
Source Code... | None. |
Some Info about the Packer/Encrypter and Author... | Author: Bart Homepage: None. Email: cryogen@free.net.pl Size of Packer/Encrypter: 6.50 KB The Packer/Encrypter itself is Packed/Encrypted with UPX v0.99 . |
Author Words about the Packer/Encrypter... | NFO is very simple executable encryptor. |
Features... | Import Table handling. Resources support. Relocation wiping. Anti API debug. Anti-W32dasm. Structured Exception Handling (SEH). Cannot be loaded using Loader.exe from SoftICE. Multilayer encryption support. |
Special stuff the Decryption Routine uses... | It performs several Structured Exception Handlers (SEH). It clears the DRx Registers to prevent Breakpoints (And maybe more then just Breakpoints?). It calls the function _PageModifyPermissions (Dunno what this does exactly ;). It also Redirects the IAT. |
The best API to Break on... | The best API to break on for the beginning: _PageModifyPermissions The best API to break on for the end: GetProcAddress+1 A little note here, if you break on _PageModifyPermissions you've got the chance that you need to Trace a lot (Or press F12 a lot ;) so you can also Break on LoadLibraryA+1. |
Recognization of this Packer/Encrypter... | Check if all the Section names are "NFO". |
Recognization Bytes... | 60 9C 8D 50 12 2B C9 B1 1E 8A |
OEP Jump... | mov eax, OEP jmp eax or
push cs or
push eax |