if we run nc rivit.dev 10011 - we'll see next text

X * 212103456793011 = 183057226632645

X = ?

Using this information and code in task.tar.gz - we can find a needed value for X

X = 9585860797856392871

https://kazuf3.github.io/portfolio/posts/ctflearn-impossible-equation/

So we need to send this value to this port. If after nc rivit.dev 10011 you'll be able to send data - just send this number.

in other case - we can send data from file. So create file with 9585860797856392871.txt name with X value content (same number as in name)

Then send this data: netcat rivit.dev 10011 < 9585860797856392871.txt

We'll see: X * 212103456793011 = 183057226632645

X = ? result: 183057226632645

CTFlearn{...}

there was no hints.. advanced mathematic knowledge is required.. and you put this in easy..

Alrighty, I solved it but in my opinion it's missing a hint if it is to be rated as easy.

? bro its supposed to be easy

yes

it'd be easy if there were a float

Hi this seemed like it should be easy to solve. I figured id start with the equation (X * 212103456793011) mod 2^64 = 183057226632645 and try solve that. any clues?

yup, just solve the equation

How did you find this equation ?

Alrighty, I solved it but in my opinion it's missing a hint if it is to be rated as easy.

there was no hints.. advanced mathematic knowledge is required.. and you put this in easy..

? bro its supposed to be easy

yes

it'd be easy if there were a float

Hard!

Is there a trick to it? I tried to find it using a loop that finds the remainder each iteration but the running time is too long. Can I get a hint? should I solve it through programming or math?

Depends. You can solve it using only math, you can combine both. Do not overcomplicate it :)

Same here, let's see how long the loop has to run.. xd There might be some math equation that doesn't require such bruteforce and is more elegant.. but I simply don't know what to look for at this point. IM gave nothing, idk

what are you doing in iteration broo..??