Linux-Unix

In this write-up we’re looking at getting into the retired machine Kotarak from Hack the Box. Kotarak was a really fun box as it required lots of different techniques and was just a longer journey to root. Our first foothold comes via leaked credentials that we can retrieve using server side request forgery. These credentials give us admin access to a Tomcat manager application where we can upload our first reverse shell. From there, we get access to both a NTDS.DIT file and a Windows SYSTEM registry hive which we can leverage to extract user hashes. Cracking these hashes, we level up to another user and eventually use a vulnerability in wget to write our SSH key into the authorized_keys file on another (virtual) host and through that get access to the root flag on there. ...

In this write-up we’re looking at solving the retired machine “TartarSauce” from Hack The Box. After spending some time on the hosted web applications, we’ll eventually get the first foothold via an outdated Wordpress plugin. From there we can upgrade to a user shell by abusing the tar command. Eventually, we get root by abusing tar once more, but this time as part of a backup script and in a bit more involved way. ...

In this post we’ll walk through the steps of getting root on the retired box “Cronos” from Hack the Box. We will discover a few subdomains by DNS enumeration and get our first shell via command injection on an admin portal suffering from SQL injection. To elevate our privileges, we will abuse a cron job set up to run as root. All in all a fun box with a lot of classic vulnerabilities. ...

In today’s write-up we’re looking at “Networked”, another Hack the Box machine rated as easy. We’ll start by finding relevant files via a directory brute-forcer, go on to read some PHP code and then exploiting a file upload feature. Command injection through a file name gives us a proper user shell, and in a second step, through network-scripts, a root shell. Enjoy! Recon We start with an nmap scan, just like in the last write-up, and see just two ports open: ...

Accessing the internet via restricted networks can be a pain. But so can be securing a network and putting those restrictions in place. Let’s have a look at how DNS tunneling can in some cases allow getting data in and out, when regular access is blocked or otherwise restricted, but DNS queries work. Seeing this technique in action can help you understand how unauthorized users could get around your security measures and use less monitored channels for communication (e.g. for malware command and control), or may come in handy when doing an attack simulation yourself. In addition, it’s a fun way to mess with captive portals which often kind of “man-in-the-middle” your connection to direct you to a sign-up page, but still let you resolve names in any state. ...