MQCyberSec

MQCyberSec Logo

MQCyberSec
Back to Writeups

Linkage

by sealldev
🚩 CTFs SecEdu CTF 2024 cryptography
Suggested: #cyberchef
Linkage / SecEdu CTF 2024
Linkage

Description

ORG-B has given us a message that is being passed around the organisation. They've found it on a few of their machines, but are unsure what it says. jvvr8--ga0/76/5;/7:/317,cr/qmwvjgcqv/0,amorwvg,cocxmlcuq,amo-. The message was signed by a mysterious "Y". Interesting.

Original Writeup on seall.dev

I put the mysterious string into CyberChef, and use Magic with Intensive mode enabled.

It finds XOR({'option':'Hex','string':'2'},'Standard',false), which decodes to an EC2 URL: http://ec2-54-79-58-135.ap-southeast-2.compute.amazonaws.com/.

Flag: SECEDU{http://ec2-54-79-58-135.ap-southeast-2.compute.amazonaws.com/}

Related Writeups

Square Power

Using p or N is outdated, let's square N!

Key Exchange

Someone wants to send you a message. But they want something from you first.

Easy Diffy

I managed to generate strong parameters for our diffie-hellman key exchange, i think my message is now safe.

Share this writeup

Contribute

Found an issue or want to improve this writeup?

Edit on GitHub