Penetration testing is the practice of conducting a cyber attack on your own network in order to identify and understand its weaknesses. Penetration testers replicate cyber assaults using the same skills and technology as hackers. Blockchains are subjected to penetration testing by developers in order to improve security. Consensus mechanism testing, wallet security tests, denial-of-service attack tests, and other types of tests are possible. FumbleChain is a blockchain that is purposely broken in order for people to hack it. It encourages users to complete challenges that highlight common blockchain security vulnerabilities.