Slides for the CharlotteJS meetup. At this meetup we talked about crazy things you can do with JavaScript.

1. wtfjs Garrett Johnson

2. _=[][(![]+[])[-~-~-~+[]]+(({}+([])))[-~+[]]+(!![]+[])[-~+[]]+(!![]+[])[+[]]],_()[(![]+[])[-~+[]]+(![]+[])[-~-~+[]]+(![]+[])[-~-~-~-~[]]+(!![]+[])[-~[]]+(!![]+[])[+[]]](({}+([]))[-~-~-~+[]+-~-~+[]]+(![]+[])[-~-~+[]]+(!![]+[])[+[]]+(({}+([])))[-~-~+[]+-~+[]]+(![]+[])[-~-~-~+[]])

3. ![]+[] == “false” !![]+[] == “true” +[] == 0 -~+[] == 1 ({}+([])) == “[object Object]”

4. “false”[1] “false”[2]“false”[4] “true”[0] “alert”

5. need to invoke “alert” somehow…. window[“alert”] will do… we need a reference to the window…

6. rumor is sort() will return the window when used out of context…

7. same idea with window[“alert”], but we can assign the method to a variable prior to invoking it to make it out of context, which makes it return the window for whatever reason… _=[][“sort”] _() == “DOMWindow”

8. getting close, we now have the sort which gives us a reference to the window, we also know how to invoke alert as a property like key, now we just need some text to alert….

9. “[object Object]”[5] “false”[2] “true”[0] “[object Object]”[3] “false”[3] “cltjs”

10. _=[][‘sort’],_()[‘alert’](‘cltjs’) is really just…

11. _=[][(![]+[])[-~-~-~+[]]+(({}+([])))[-~+[]]+(!![]+[])[-~+[]]+(!![]+[])[+[]]],_()[(![]+[])[-~+[]]+(![]+[])[-~-~+[]]+(![]+[])[-~-~-~-~[]]+(!![]+[])[-~[]]+(!![]+[])[+[]]](({}+([]))[-~-~-~+[]+-~-~+[]]+(![]+[])[-~-~+[]]+(!![]+[])[+[]]+(({}+([])))[-~-~+[]+-~+[]]+(![]+[])[-~-~-~+[]])

12. Thanks! Resources http://badassjs.com/post/2929065287/obfuscation http://news.ycombinator.com/item?id=1154435 http://adamcecc.blogspot.com/2011/01/javascript.html