Tags: reversing 

Rating: 4.0

# REV2
Challenge :
![](https://github.com/mali44/CTF-Write-ups/blob/master/2018-03-21-angstromctf/rev_2/rev_2.png?raw=true)

Firstly to be aware of what strings in it I run strings command and check out the flaw. Found that:
![](https://github.com/mali44/CTF-Write-ups/blob/master/2018-03-21-angstromctf/rev_2/rev2%20images/rev2_Strings.png?raw=true)
I see there are two levels of reaching the flag out. In this case let go through:
yeah just like what hint said I went to radare2 and analyze the main function..

```
r2 -d ./rev2_32
[0xf7f79c70]> aaaa #analyze all file
[0xf7f79c70]> pdf@main
```
Here is first we need to look:
![](https://github.com/mali44/CTF-Write-ups/blob/master/2018-03-21-angstromctf/rev_2/rev2%20images/rev2_radare_main_1.png?raw=true)

Now take attention over here row:
```
0x08048546 3dd7110000 cmp eax, 0x11d7
0x0804854b 741e je 0x804856b
```
Our first input get compared with 0x11d7. What that mean is in decimal system= 4567
If I do enter random one it'd take me through
```
0x08048554 6834870408 push str.Sorry__your_guess_of__d_was_incorrect._Try_again
```
So I pass easily to second level. By that mean is we jump to address 0x804856b.
Level 2 question is asked as you can see in the image above.
We enter second input/S cuz just like in question it want 2 inputs from us

##But A rule there is !
Firstly both of our inputs get controlled if the both are in between 9

Original writeup (https://github.com/mali44/CTF-Write-ups/blob/master/2018-03-21-angstromctf/rev_2/README.md).