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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.
🚩 FLAG
```
404CTF{L3s_0r4cl3s_RSA_s0n7_si_fr4g1l35}
```
---
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