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# Un simple oracle \[1/2]

**Category:** Cryptanalysis - **Points:** 981 - **Difficulty:** Easy - **Solves:** 150

**Description:**

Bonjour agent, Nous avons découvert un étrange service ouvert sur un des serveurs de **Hallebarde**. Il semble possible d'interagir avec lui. Pourrriez-vous récupérer son secret?

`nc challenge.404ctf.fr 32128`

**Solution:**

This cryptanalysis challenge is solved using a basic RSA attack: the Chosen Plaintext Attack. To do this, I used a tool called RSHack and I simply entered the public key parameters and sent a request to the oracle to calculate, with the help of the tool, the ciphertext-plaintext relation and thus decrypt the message.

<details>

<summary>🚩 FLAG</summary>

```
404CTF{L3s_0r4cl3s_RSA_s0n7_si_fr4g1l35} 
```

</details>