Tags: crypto
Rating:
# base646464
Author: [roerohan](https://github.com/roerohan)
Base 64, base 64, base 64 ... 25 times.
# Requirements
- Basic Knowledge of Node.js
# Source
- [generate.js](./generate.js)
- [cipher.txt](./cipher.txt)
# Exploitation
You have to decode base64 25 times.
```javascript
// Flag is base 64 encoded 25 times
let ret = flag;
for(let i = 0; i < 25; i++) ret = btoa(ret);
```
Of course, you can use bash XD:
```bash
cat cipher.txt | base64 -d | base64 -d |base64 -d | base64 -d
| base64 -d | base64 -d | base64 -d | base64 -d | base64 -d | ba
se64 -d | base64 -d | base64 -d | base64 -d | base64 -d | base64
-d | base64 -d | base64 -d | base64 -d | base64 -d | base64 -d
| base64 -d | base64 -d | base64 -d | base64 -d | base64 -d
flag{l00ks_l1ke_a_l0t_of_64s}
```
You can use python too:
```python
>>> f = open('cipher.txt').read()
>>> import base64
>>> for i in range(25):
... f = base64.b64decode(f)
...
>>> print(f)
b'flag{l00ks_l1ke_a_l0t_of_64s}'
```
The flag is:
```
flag{l00ks_l1ke_a_l0t_of_64s}
```
