Category: cryptography
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Before starting, let me introduce two terms used in the title: There are multiple of attacks, that exploits lack of padding in textbook RSA: Here you can find script exploiting no padding vulnerability: https://github.com/o-lenczyk/rsa/blob/master/no_padding_attacks.py sample output: Regardless of the key size, lack of padding is critical textbook vulnerability. In all…
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In previous post I was testing and comparing different factorization algorithms. Based on my observation, the two most critical factors determining the time required to crack private key are bit length Most straightforward factor. Most of the known algorithms has exponential complexity. So factoring 2048bit number is not twice as…
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As said before, RSA algorithm rests on simple fact: multiplying two large numbers is easy, but factoring the result into original primes is incredibly difficult. Lets see how difficult it is. I prepared tool for that: https://github.com/o-lenczyk/rsa/blob/master/crack_rsa.py and did the measurements using my pc (11th Gen Core i7-11370H) In RSA,…
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In a previous post, I introduced the RSA algorithm and outlined its importance. Here, I will present a naive Python implementation. Later, I will highlight its shortcomings and address the flaws. The code can be found here: https://github.com/o-lenczyk/rsa Lets explain two helper functions: This function computes greatest common divisor. Example:…
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RSA stands for Rivest-Shamir-Adleman, who first described the algorithm in 1977. It is used in public-key cryptography. RSA is essential for modern internet protocols. Key applications are Public key cryptography RSA is asymmetric encryption algorithm. This means it uses pair of keys Public key is used for encryption, private key…