Stratosphere flight. How to crack Struts using an Action app and create a Forward Shell

Today, I will show how to conquer the stratosphere – i.e. gain root access on the Stratosphere VM available on Hack The Box CTF grounds. To capture the root flag, I will have to overcome the Apache Struts framework to get an RCE vulnerability in a web app, put to practice the rarely used (but still very useful) Forward Shell remote session concept, highjack a library, and find a way to exploit the eval() function in a treacherous Python script.

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The PWN realm. Modern techniques for stack overflow exploitation

The buffer overflow vulnerability is an extremely popular topic on hackers’ forums. In this article, I will provide a universal and practically-oriented ‘introduction’ for enthusiasts studying the basics of low-level exploitation. Using stack overflow as an example, I will address a broad range of topics: from security mechanisms currently used by the GCC compiler to specific features of binary stack overflow exploits.

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Compressed Token Format (CTF). One-time passwords, LDAP injections, and tricks with 7z archiver

Today, I will explain how to hack the CTF virtual machine available on Hack The Box training grounds. For the purposes of this article, the abbreviation “CTF” refers to Compressed Token Format, not Capture the Flag. This VM is vulnerable to various types of LDAP injections, while its authentication mechanism is based on stoken, a generator of one-time passwords. In addition, the target machine uses a loose Bash script, and I will exploit it to fool the 7z archiver and gain root access.

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Diabolically reddish pentest. Building tunneling chains through docker containers on a Hack the Box virtual machine

How to seize control over a host located in a different subnetwork? The right answer is: build numerous intricate tunnels. This article addresses tunneling techniques and their application in pentesting using as an example Reddish, a hardcore virtual machine (insane difficulty level: 8 out of 10) available on Hack The Box training grounds.

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The great mischief. Working your way to the root flag through IPv6 labyrinths on a Hack the Box virtual machine

In this article, I will explain how to gain superuser privileges on Mischief VM available on Hack The Box training grounds. During this journey, you will acquire some SNMP skills, understand the IPv6 routing principles, and learn how to deal with the access control list (ACL) regulating the files and folders permissions. In the end, I will show how to write an ICMP shell in Python and test it.

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