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Linkage

by sealldev
🚩 CTFs SecEdu CTF 2024 cryptography
Suggested: #xor #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/}

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