In this post, I’m going to solve the SpamLess challenge from UUTCTF2021. It is about sending an email without being spam to [email protected] address. The mail server is served as a Tor’s hidden service.

Now the writeup …

The Challenge

SpamLess Challenge

I’ve described the needed tools and methods for solving the question in the following video. You can check my previous post about fetching a hidden service’s public key which is needed for solving this challenge.

SpamLess WriteUp – UUTCTF2021

If you have any question, you can reach me by email.

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Offsec is an Iranian computer security group which holds conferences or CTFs in the computer security area. In their recent challenge, they created a web challenge which is accessible through offsecmag Telegram channel. The challenge started on 16 Dec 2016 and here I will WRITE UP! 🙂

In this post, the write up of the challenge is presented.

Continue reading Catch the CORS Write Up!

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