The WTF effect

Lol, don't worry. delete this ;\
I was just wondering why when you md5(NULL) it is different to md5(0) or NULL+NULL, when they work out the same without md5ing...

 

md5(0) and md5(NULL+NULL) return the same thing because when using the + operator on a NULL value, the interpreter (probably php in your case) turns that NULL into a 0. 0+0=0.

The reason md5(NULL) doesn't do the same thing is because NULL is an empty string (also still assuming it's php). md5 still returns hashes even on an empty string (null) . If you cast a null to an int, you'll get the previous value, of md5(0).

 

Makes much sense. I asked a 'supposed' security expert and he just laughed at me lol.