Crack unsafe RSA Encryption

I had to decrypt a weak RSA encrypted message. Why weak? Because a (only) 268-bit key was used for encryption. So RSA is not bad, but please use a suitable key size. For this blog post it’s not important, why RSA is secure and works, it’s just a tutorial how to calculate a private key if it get’s lost (will just work for unsecure keys indeed) or to demonstrate that small key sizes are unsecure....

December 24, 2015 · 3 min · Christian Hotz-Behofsits