Top 2 Disassemblers

sumber: http://sectools.org/disassemblers.html

1. IDA Pro : A Windows or Linux disassembler and debugger
Disassembly is a big part of security research. It will help you dissect that Microsoft patch to discover the silently fixed bugs they don't tell you about, or more closely examine a server binary to determine why your exploit isn't working. Many disassemblers are available, but IDA Pro has become the de-facto standard for the analysis of hostile code and vulnerability research. This interactive, programmable, extensible, multi-processor disassembler now supports Linux (console mode) as well as Windows.

2. OllyDbg : An assembly level Windows debugger
OllyDbg is a 32-bit assembler level analyzing debugger for Microsoft Windows. Emphasis on binary code analysis makes it particularly useful in cases where source is unavailable. OllyDbg features an intuitive user interface, advanced code analysis capable of recognizing procedures, loops, API calls, switches, tables, constants and strings, an ability to attach to a running program, and good multi-thread support. OllyDbg is free to download and use but no source code is provided.