Reverse shell of 237 bytes. How to reduce the executable file using Linux hacks

Date: 15/02/2022

Once I was asked: is it possible to write a reverse shell some 200 bytes in size? This shell should perform the following functions: change its name and PID on a regular basis, make you coffee, and hack the Pentagon… Too bad, this is most likely impossible. But the task seemed interesting and challenging to me. Let’s see whether it can be implemented.
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Kernel exploitation for newbies: from compilation to privilege escalation

Date: 09/02/2022

Theory is nothing without practice. Today, I will explain the nature of Linux kernel vulnerabilities and will shown how to exploit them. Get ready for an exciting journey: you will create your own Linux kernel module and use it to escalate your privileges to superuser. Then you’ll build a Linux kernel with a vulnerable module, prepare everything required to run the kernel in a QEMU virtual machine, and automate the kernel module loading process. Finally, you will learn how to debug the kernel and use the ROP technique to gain root privileges.
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Secrets of V8 Engine. Dissecting Chrome on a Hack The Box virtual machine

Date: 30/12/2021

No, this article isn’t about motor cylinders and valves – it’s about Google V8 Engine used in Chromium and Android. Today, I will show how to hack it on RopeTwo, the most hardcore VM on Hack The Box. Concurrently, you will learn what types of data are used in this engine, how to manipulate them in order to drop an exploit, how to use V8 debugging tools, what it WebAssembly, and how can it be used to penetrate into the RopeTwo shell.
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