Medium Live


50 points

15 Solves



kcbowhunter ctflearn++ badge

Community Rating: 4.67 / 5

This challenge combines forensics, crypto and programming. A 4096 bit RSA key is used to encrypt the flag and both the encrypted key and the encrypted flag are hidden inside the jpeg. Python scripts are also provided to help decrypt the RSA key which is xor'd with bytes from the jpeg. These same Python scripts can be used as part of solving my 100 point Scope challenge. Good Luck! You may want to solve my MountainMan challenge first if you are having difficulty finding the key and flag hidden in the jpeg.

First 10 Solvers

Rank Username
1 mamimi1773
2 Rivit
3 ill_advisor
4 ebouteillon
5 bobo1239
Rank Username
6 Ntoskrnl
7 shikame
8 c4r0
9 Gilad ctflearn++ badge
10 SHaNTuDe

  • Rivit

    Nice photo! and challenge too ;)

  • keteik

    Does the Jakarta.pem.xor should be bytes between ffd9 markers?

    • kcbowhunter ctflearn++ badge

      Yes... you can generate your own 4096 bit RSA key to check the file sizes

  • V1L3N

    Here after completing MountainMan, can i get a hint to begin? @kcbowhunter

    • kcbowhunter ctflearn++ badge

      Read through the comment blocks and find the story that outlines the solution