Tags: reverse-engineering binary 

Rating:

# In Plain Text (Binary RE 50)

We're given an file. Let's look at its type.

```
$ file challenge
challenge: ELF 32-bit LSB shared object, Intel 80386, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux.so.2, for GNU/Linux 3.2.0, BuildID[sha1]=63c841da3195b526943ba730cad66392c5dae087, not stripped
```

Looks like it's an executable file, which makes sense since this is in the Binary RE category. Let's see what happens when we run it.

```
$ chmod +x challenge
$ ./challenge
Hey there, I know I am the challenge and all, but I forgot what the flag was...
Could you just tell me the flag real quick? Please?
That doesn't sound familiar... :/
```

One of the first things I do whenever I run into a low-difficulty Binary RE problem like this is to just run `strings` on it. Let's see if the flag is in there somewhere.

```
$ strings challenge | grep "MCA{.*}"
MCA{y3ah_sur3_here_y0u_g0}
```

Original writeup (https://github.com/shawnduong/ctf-writeups/blob/master/2019-MITRE-STEM/In-Plain-Text.md).