K9

Connecting to Hidden Mail Server using Android


My Contribution in K9 Android Mail Client

My Contribution in K9 Android Mail Client

K-9 is an attractive, open-source email client for Android with support of IMAP, POP3, SMTP, and exchange protocols. Hence, this client does not support proxy feature. This problem is referenced in #704 #980 #2619. In this post I will talk about my contribution in K-9 project by adding SOCKs proxy feature, which can be used for connecting hidden mail services.

In previous post, I described about connecting Thunderbird, an open source email client for PC, to a hidden mail service. In this post I will talk about modifying K-9 mail and connecting Android client to the hidden mail service.

TorBird

Connecting to Hidden Mail Server

In the previous post, I’ve talked about configuring a hidden email server using hMailServer. In this post I will talk about how to access this hidden Email server. I’m using ThunderBird as email client, tajbakhsh.fake as the fake domain of email server (and accounts), two users ([email protected] and [email protected]).

During all the processes, I assume that the email server is configured as previous post and client has access to the TOR network.

Onion hMailServer

Configuring a Hidden Email Server

In this post, I will talk about configuring an Email server which is accessible using TOR. Using TOR will make its IP to be hidden, also accessible if it is behind NAT (inside a home computer without a public IP). But the main question is why one should use this kind of scenario?

Many people may not trust messaging services such as Telegram or WhatsApp but want to have their own private communication system. In this tutorial, you can run your own mail server in your home LAN and access it through Internet without spending money for public IP or VPS.

For the email server part, I will use hMailServer, an open source email server developed for windows.

IlamCTF

Ilam CTF: Android Reverse WriteUp

Ilam CTF has been hold on 23rd Nov 2018. Unfortunately I’ve planned other things for 22-23 Nov 2018 and because of the delay in holding the CTF, I couldn’t attend this CTF.

However, I could download the Android Reverse question for future analysis. And the flag is here:

ilam_ctf_0a095194dbcf4f798751aaafdfb_1db6b2ed339f4698b6b38b5e7ae

But the WriteUP!