PETEP (PEnetration TEsting Proxy)
GitHub: https://github.com/Warxim/petep
Website: https://petep.warxim.com/
PETEP is an open-source TCP/UDP Proxy with support for modifying the transmitted data in graphical interface manually or using automatic rules. PETEP has multiple features including filterable History of transmitted data, automatic tagging based on simple rules, resending traffic and scripting own automatic traffic modification code.
If the current features are not enough, you can always extend the PETEP functionality by using well-known HTTP proxies (e.g. Burp, Zaproxy) and modify the binary protocols inside these, since PETEP allows you to wrap binary communication in HTTP.
