Tags: icectf 318br pt-br 

Rating: 1.0

#Hidden in Plain Sight

Primeiro, baixamos o binário
wget -c https://play.icec.tf/problem-static/828644c3ad8ccfa14b86a69dccd36f2b-plain_sight_df5d2c1da50110458fa00d0db6586b23cd67317c7f7b95f4a092d645a4570296 -Oplain-sight

Nem me dei ao trabalho de executá-lo. Já abri direto no gdb:

```
gdb plain-sight

(gdb) disas main

0x0804851b <+112>: mov $0x49,%al
0x0804851d <+114>: mov $0x63,%al
0x0804851f <+116>: mov $0x65,%al
0x08048521 <+118>: mov $0x43,%al
0x08048523 <+120>: mov $0x54,%al
0x08048525 <+122>: mov $0x46,%al
0x08048527 <+124>: mov $0x7b,%al
0x08048529 <+126>: mov $0x6c,%al
0x0804852b <+128>: mov $0x6f,%al
0x0804852d <+130>: mov $0x6f,%al
0x0804852f <+132>: mov $0x6b,%al
0x08048531 <+134>: mov $0x5f,%al
0x08048533 <+136>: mov $0x6d,%al
0x08048535 <+138>: mov $0x6f,%al
0x08048537 <+140>: mov $0x6d,%al
0x08048539 <+142>: mov $0x5f,%al
0x0804853b <+144>: mov $0x49,%al
0x0804853d <+146>: mov $0x5f,%al
0x0804853f <+148>: mov $0x66,%al
0x08048541 <+150>: mov $0x6f,%al
0x08048543 <+152>: mov $0x75,%al
0x08048545 <+154>: mov $0x6e,%al
0x08048547 <+156>: mov $0x64,%al
0x08048549 <+158>: mov $0x5f,%al
0x0804854b <+160>: mov $0x69,%al
0x0804854d <+162>: mov $0x74,%al
0x0804854f <+164>: mov $0x7d,%al

```

Bastava copiar esse trecho e colar num arquivo, nesse caso, chamado "file"

Então fazer essa função em bash:

```
hex2ascii(){
i=0
while (( $i < ${#1} )); do
echo -en "\x${1:$i:2}"
let i+=2;
done
echo;
}
```
e por fim:
```
for i in $(grep mov file | cut -f3 -dx | cut -f1 -d,) ; do hex2ascii $i; done | tr -d '\n'
```
IceCTF{look_mom_I_found_it}

norajAug. 26, 2016, 11:48 p.m.

Writeup is not in english


norajAug. 26, 2016, 11:48 p.m.

writeup is not in english