TLS-Attacker is a Java-based framework for analyzing TLS libraries. It can be used to manually test TLS clients and servers or as as a software library for more advanced tools.
tls-attacker/TLS-Attacker has 881 GitHub stars.
It currently ranks #12769 daily, #13783 weekly, #11503 monthly by momentum on Trending Repos; its best-ever rank is #5397.