Inctf Quals 2018-MultiPrime RSA WriteUp

This year InCTF Quals really went well and I feel extremely privileged to be a part of it and conduct it. I hope everyone learned a lot more stuff after this CTF. This blog post covers the intended solution of the challenge that I created: MultiPrime RSA. It was a medium level challenge with 3 …

Advertisement

Revolutional Secure Angou WriteUp

CTF: TWCTF 2018 CATEGORY: CRYPTO POINTS: 154 This blog post is for discussing the exploit of the challenge Revolutional Secure Angou. We were given the following ruby script When we go through the above code, we can see that the prime q is generated in a different way rather than usual. q = OpenSSL::BN.new(e).mod_inverse(p) On …

CBC Bit-Flipping Attack

This blog post is for the discussion of AES CBC Bit-flipping attack. Firstly, get familiar with the CBC mode of encryption before you go through this attack. Please do refer the below blog post to get an idea about CBC mode. link: CBC mode of encryption This attack is explained with the help of Cryptopals Challenge16 …

ECB Byte At A Time

This blog post is about AES ECB Byte At A Time attack. If you don't have any prior knowledge regarding AES ECB please do refer to it, so that the attack will be understood clearly. Some Important Points Regarding AES AES is a block cipher, each block of size 16bytes long If the length of …

Common Modulus Attack

In this blog we are going to take a look at one of the popular attacks on RSA, Common Modulus Attack. As the name suggests, this attack works when a common modulus but different encryption exponents such that their gcd is 1 are used. Let us consider a scenario for better understanding. Person A wants …