# QmFzZTY0

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**Category:** Cryptography - **Points:** 500 (at the beginning) then 10 (at the end) - **Solves:** 640\
**Description:** We found this message : can you decipher it? `qiPGS{3apElcg1ba_1f_r4fl}`

**Infos:**

> A .txt file is provided (file.txt)

**Solution:**\
To solve this challenge you need to decrypt the message.\
With the title chall, we quickly find that the encryption is in link with Base64.

So when we go on ([CyberChef](https://gchq.github.io/CyberChef/)) and copy/paste the encrypted message, we can see that the content is reduce.\
We continue to decrypt by add more "From Base64" block. And after **20** blocks the flag is displayed.

I also created a python program to do that (decode.py)

<details>

<summary>🚩 FLAG</summary>

```
dvCTF{Base64_Is_The_Best}
```

</details>