This paper discusses the obstacles that stand in the way of doing a good job of machine-code analysis. Compared with analysis of source code, the challenge is to drop all assumptions about having certain kinds of information available (variables, control-flow graph, call-graph, etc.) and also to address new kinds of behaviors (arithmetic on addresses, jumps to ``hidden'' instructions starting at positions that are out of registration with the instruction boundaries of a given reading of an instruction stream, self-modifying code, etc.).

The paper describes some of the challenges that arise when analyzing machine code, and what can be done about them. It also provides a rationale for some of the design decisions made in the machine-code-analysis tools that we have built over the past few years.

(Click here to access the paper: PDF; (c) Springer-Verlag.)