# Challenge Name: Revision


## Detailed solution

http://git.ritsec.club:7000/Revision.git/

Starting by cloning the Revision repository

```
git clone http://git.ritsec.club:7000/Revision.git/
```
```
ls -la
total 244
drwxr-xr-x 8 kali kali 600 Apr 12 14:30 .
drwxr-xr-x 16 kali kali 540 Apr 12 14:29 ..
-rw-r--r-- 1 kali kali 3135 Apr 12 14:30 about.html
-rw-r--r-- 1 kali kali 606 Apr 12 14:30 alumni.html
drwxr-xr-x 6 kali kali 120 Apr 12 14:30 assets
-rw-r--r-- 1 kali kali 15 Apr 12 14:30 CNAME
-rw-r--r-- 1 kali kali 203 Apr 12 14:30 _config.yml
-rw-r--r-- 1 kali kali 307 Apr 12 14:30 contact.html
drwxr-xr-x 2 kali kali 200 Apr 12 14:30 _data
-rw-r--r-- 1 kali kali 1511 Apr 12 14:30 donors.html
-rw-r--r-- 1 kali kali 900 Apr 12 14:30 eboard.html
-rw-r--r-- 1 kali kali 1124 Apr 12 14:30 events.html
-rw-r--r-- 1 kali kali 838 Apr 12 14:30 Gemfile
-rw-r--r-- 1 kali kali 1482 Apr 12 14:30 Gemfile.lock
drwxr-xr-x 8 kali kali 260 Apr 12 14:30 .git
-rw-r--r-- 1 kali kali 57 Apr 12 14:30 .gitignore
drwxr-xr-x 2 kali kali 260 Apr 12 14:30 _includes
-rw-r--r-- 1 kali kali 371 Apr 12 14:30 index.html
drwxr-xr-x 2 kali kali 100 Apr 12 14:30 _layouts
-rw-r--r-- 1 kali kali 1718 Apr 12 14:30 links.html
-rw-r--r-- 1 kali kali 1011 Apr 12 14:30 newsletters.html
-rw-r--r-- 1 kali kali 704 Apr 12 14:30 past-eboards.html
-rw-r--r-- 1 kali kali 381 Apr 12 14:30 README.md
-rw-r--r-- 1 kali kali 604 Apr 12 14:30 resources.html
drwxr-xr-x 2 kali kali 40 Apr 12 14:30 ritsec.github.io
-rw-r--r-- 1 kali kali 532 Apr 12 14:30 signin.html
-rw-r--r-- 1 kali kali 644 Apr 12 14:30 signup.html
-rw-r--r-- 1 kali kali 163322 Apr 12 14:30 sponsorship.pdf
-rw-r--r-- 1 kali kali 2496 Apr 12 14:30 sponsors.html
-rw-r--r-- 1 kali kali 210 Apr 12 14:30 tasks.txt
```

We have some files and the .git folder

```
ls -la
total 44
drwxr-xr-x 8 kali kali 260 Apr 12 14:30 .
drwxr-xr-x 8 kali kali 600 Apr 12 14:30 ..
drwxr-xr-x 2 kali kali 40 Apr 12 14:29 branches
-rw-r--r-- 1 kali kali 266 Apr 12 14:30 config
-rw-r--r-- 1 kali kali 73 Apr 12 14:29 description
-rw-r--r-- 1 kali kali 23 Apr 12 14:30 HEAD
drwxr-xr-x 2 kali kali 300 Apr 12 14:29 hooks
-rw-r--r-- 1 kali kali 28350 Apr 12 14:30 index
drwxr-xr-x 2 kali kali 60 Apr 12 14:29 info
drwxr-xr-x 3 kali kali 80 Apr 12 14:30 logs
drwxr-xr-x 16 kali kali 320 Apr 12 14:29 objects
-rw-r--r-- 1 kali kali 1038 Apr 12 14:30 packed-refs
drwxr-xr-x 5 kali kali 100 Apr 12 14:30 refs
```
Checking the git log with ```git log -p``` i found some commits for flag.txt

We can use -- flag.txt to see only the file updates

```
git log -p --all --full-history -- flag.txt
```

The last commit show that the flag.txt has been deleted


Checking the first commits


As we can see in each commit we have an update for the file, removing the existed charactere and add a new one

We know that the flag format is RS{} so we need to combine file updates to get the flag

Let's get only the insertion(+) updates from the git log output

```
git log -p --all --full-history -- flag.txt | grep -x '.\{2\}' | grep "^+" | cut -c 2-
```

```
}
s
m
0
c
_
t
i
g
_
3
s
0
h
t
_
d
e
t
p
1
r
c
s
_
u
0
y
_
3
p
0
h
_
I
{
S
R
```

Let's save the output in a file and use a little python script to get our flag RS{}

```python
f = open("flag.txt")

flag = f.read().replace('\n', '')[::-1]

print(flag)
```

## Flag

```
RS{I_h0p3_y0u_scr1pted_th0s3_git_c0ms}
```

Original writeup (https://github.com/BaadMaro/CTF/blob/main/RITSEC-CTF-2021/Revision).