Crypto
Before diving right into more advanced attacks, let’s take a minute to do a quick recap because it’s been a long time since the last part. Once your mind is warmed up you can safely move on.
On the program today you have :
- Small public exponent
- Hastad broadcast attack
- Fermat’s attack
- Wiener’s attack
RSA is my favorite cryptosystem. It’s simple and powerful.
In this series I will try to go through every attacks (that I’m aware of) against RSA which are useful for solving CTF tasks. I’m not going to give you scripts that will do all the work for you but rather explain how the attacks work. The aim of this series is to understand the attacks you use and which one is most appropriate depending on the task. I will try to be beginner friendly and repeat myself in the beginning but afterwards I will assume that the reader has learnt the concepts.
Our first attacks will be :
- Common modulus
- Decipher oracle
The objective of this challenge is to find a way to get logged in as the user “administrator”.
This is the demo application for our new session management system based on military cryptography (namely CBC-MAC). You can log in as any user (except ‘administrator’) with the password ‘Password1’. We blocked access to ‘administrator’ account for security reasons.
By his grace, we have been successfully organizing nullcon, year on year and this is the Nullcon9. At this juncture we cannot forget what did he had said, the one panacea given by him…
In 2010 when we were all worried, how can we be successful with this first ever event…