Optimizing away JavaScript obfuscation 

Javascript Malware, heavily obfuscated by author

apply static analysis to strip it back to bare minimum and figure ut what its doing 


Compiler Theory -> deobfus process
sematic trnasformations

not pretty-printing, ensure the semantics and preserved

UGLIFYJS -> inserting newline, indentation, whitespace , 

run SAFE to generate Abstract Syntax Tree

Obfus:
"price = $" + 10 (int convert to str) = "price =$10"
10 - true = 9 (bool convert to 1)

!true * 9 = 0 (!true = 0)

substitue code and delete unused variables

Simplify AST

techniques are same, can build your own deobfuscater, similar to compiler