Unzipped the provided file and got an encrypted.txt file


Considering we have the same ```n``` and two different ```e``` and ```c``` means this should be a Common Modulus attack. The title of the challenge hints at it as well.

I converted the hex strings into int using python.


I'm not great at scripting crypto stuff but I did find this script.

https://raw.githubusercontent.com/a0xnirudh/Exploits-and-Scripts/master/RSA%20Attacks/RSA%3A%20Common%20modulus%20attack.py

After fixing the identation issues, I pasted the n, c1,c2, e1 and e2 and I ran the script and I got a decimal value.

I modified the script some more to convert the decimal value to hex and then to ASCII.



HTB{c0mm0n_m0d_4774ck_15_4n07h3r_cl4ss1c}

Original writeup (https://github.com/LazyTitan33/CTF-Writeups/blob/main/HTB%20-%20Cyber%20Santa%20is%20Coming%20to%20Town%202021/Crypto/Common%20Mistake.md).