Showing impossible to understand Javascript: Obfuscated Quine
oim.ae
oim.ae
var f = []['concat']; (f + '');
// Chrome
"function concat() { [native code] }"
// IE (9)
"
function concat() {
[native code]
}
"
This script tries to extract letters from that string representation, which fails if the string is different. (This is also used as an anti-debugging measure in some JS malware, to prevent researchers from replacing document.write with alert() or similar.)2. Iterating over the window object doesn't work the same way in IE: http://blogs.msdn.com/b/ericlippert/archive/2005/05/04/41468...
In particular, this script tries to extract strings 'sessionStorage', 'getComputedStyle', 'onchange' by iterating over the window object, all of whom fail in IE.
var f = []['concat']; // Array.prototype.concat
f()[0]; // returns the global window
The rest of the script appears to mostly be old tricks - convert stuff to strings, combine characters in strings to compose expressions, pass them to eval...