SMIC (2)

intro crypto RSA FCSC 2020 solved on

Description

The security of the RSA cryptosystem relies on a well-known computational problem.

Your goal is to decrypt the “ciphertext” c given below to recover the correspondong “plaintext” message m using the given public key (n, e).

Values:

e = 65537
n = 632459103267572196107100983820469021721602147490918660274601
c = 63775417045544543594281416329767355155835033510382720735973

The flag is FCSC{xxxx}, where xxxx has to be replaced by the value of m written in decimal.

A variant of this challenge is available here: SMIC (1).

Author

Flag

You don't have JavaScript actived. No problem! You can check your flag like this: echo -n 'PUT_THE_FLAG_HERE' | sha256sum # possible output: cd199534760dc450fbe720d9a4ebb1f4e7caa9663a22fabb11786f1946242bd9

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Date	Author	Language	Tags	Vote
2023-12-04	BuzzYbis	🇫🇷

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