https://github.com/openwall/john
CTF | Hashes | Tools
John the Ripper is THE tool to brute force passwords and password hashes. It is very fast in calculating hashes with support of GPU acceleration and supports a wide range of different hash formats.
https://default-password.info/
CTF | Datasets
The website features a large list of default passwords found in routers and IoT devices. The data is sorted by manufacturer and can be searched.
These websites have access to large rainbow tables and allow quick access to known weak hashes.