662a73fda562ef06c3b52edc

About

One of the easiest crackme’s i’ve worked on. link is here.

Diving in

opened this fucked binary using ida. looks very intimidating ngl. At fist i thought this was heavily obfuscated but once u reach the print statements and start tracking back, you’ll realise how shit this fuck is.

so now going to the print statements (renamed by me)

now to get into the else, v61 must be negative. so, let’s audit v61

as you can see, rax has our input, so renamed it to input_apna

now based on the logic inside while, v59 has to be 0 for *input_apna to increment. which means,

*(_QWORD *)(((unsigned __int64)&v63 & 0xFFFFFFFFFFFFFFE0ui64) + 0x18) - (_QWORD)input_apna;

has to be 0. interesting this is that *(_QWORD *)(((unsigned __int64)&v63 & 0xFFFFFFFFFFFFFFE0ui64) + 0x18) is some ASCII bullshit as you can see here

so therefore, i entered this ascii bullshit as input :

et voilà!