## RSA

RSA is one of the most common modern cryptosystems, known for it's public and private key encryption. If you see public and private keys, there is a strong chance that it is an RSA problem, or at least RSA derived.

Some RSA problems will not be solved by default RSAtool runs. For those, you will often need an extension named Sage Math. I keep a cloud server setup with a few crypto tools and Sage installed, and a ton of cores and vmem so that if I need to, I can turn it on, download the ciphers, brrrrrrrrrt and solve with zero effort. Definitely a CTF power move, and it is free as long as you remember to turn it off once you are done, because it costs about $1.20 a minute. If you forget to turn it off, you'll burn through your free credits instantly and then have an$1000 dollar bill at the end of the month.