In fact, it used to be standard practice back in the 1970’s and 1980’s, before the Internet and ubiquitous broadband connectivity, to manually patch operating system code and programs in this manner as the source code was proprietary and never distributed to end-users. Having done considerable assembly language and systems programming in the past, I can vouch for how easy this process is as I have done it myself to patch binary code for operating systems and application programs. The presenter shows, by analyzing the assembly code, how easy it is to crack a password-protected application by simply patching (editing) the application’s binary code directly, replacing the binary code to test for a valid password with NOP (no operation) commands, and then re-running the application from within OllyDbg. When an application is opened with OllyDbg, it presents the user with panels which contain a memory address, the application’s binary code (in hex), the assembly language representation of the binary, and a panel displaying text strings found in the binary code. This particular video demonstrates the use of the tool to crack password-protected applications. Binary code analysis programs are extremely useful for debugging programs when source code is available. It can also locate routines from object files and libraries.

It can trace registers, recognize procedures, API, switches, tables, constants, and strings. OllyDbg is an 32-bit binary code analysis debugger program for Microsoft Windows created by Oleh Yuschuk (hence the name). Bschmid5 at May 08,2017 This video was uploaded on Augand is the first of a series of tutorials on OllyDbg.

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