Medium
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These numbers were scratched out on a prison wall. Can you help me decode them? https://mega.nz/#!al8iDSYB!s5olEDK5zZmYdx1LZU8s4CmYqnynvU_aOUvdQojJPJQ

#### First 10 Solvers

Rank | Username |
---|---|

1 | voidmercy |

2 | limyunkai19 |

3 | nandayo |

4 | emperorlepone |

5 | ross3102 |

Rank | Username |
---|---|

6 | greglatronica |

7 | krispursiainen |

8 | aglickman |

9 | niclev20 |

10 | daniellacalle |

## Peder

[REDACTED] This comment is only shown to users who have solved this challenge.

## FelixGB

I'm totally new to RSA algorithm. I read the RSA Wiki and saw the equations ... not sure if we are suppose to simply try to figure out P / q or if we really need them or suppose to try to decode the equations? So far ... I've spent hours and still on square 1 >.<

## intelagent

Check out the Wikipedia article for rsa cryptosystem!

## pjrox

Note that Crypto.Util Library is a must to solve RSA... I too found it out today

## korsasupreme

Solved this call on Go, on python it would be much easier.

## QuintusJoyal

RsaCtfTool.py

## intelagent

Way overdoing it for this challenge!

## DarkStar

cool

## 95ych

lol , rip RSA sense for that value of e

## c0conut

Great RSA challenge

## wojtek9022

After 2 hours of searching i was frustrated, but after all I pretty happy that i didn't give up and i learned something new

## sharkmagic07

[REDACTED] This comment is only shown to users who have solved this challenge.

## Ebhodini

How to calculate phi(n) when n is so enormous?

## Crucizer

I don't think that the value of phi(n) depends on n. You can use the formula (p-1)(q-1) to calculate phi(n).

## Crucizer

Okay, I just realised p,q weren't given so, can you tell me how to calculate n?

## CVCodes

It seems the question has n as being phi(n) already as it seemed to work still with just using the n value given in the question to get the flag

## Jeltzin

[REDACTED] This comment is only shown to users who have solved this challenge.

## the_condor

This is same as rsa in hard part!!

## Crucizer

Can anybody tell me what does the 'c' no, stands in the text? I can understand the 'd' and 'e' numbers, but not the 'c' one.

## gonzz

It's the cyphertext

## Anonymousdestroyer

EASY PEASY

## Theriphunters

[REDACTED] This comment is only shown to users who have solved this challenge.

## warmachine86

[REDACTED] This comment is only shown to users who have solved this challenge.

## technophobian

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## arklegru

It turns out, if you take a shortcut you don't need to calculate phi, p, or q.