Reverse engineering *

Imagine someone withdrew money from a company's account at night. The next morning panic breaks out, leading to yet more problems. The IT department can reinstall a compromised system from scratch or restore it from backup. Reinstalling from scratch will wipe out all traces left by the attackers, and external investigators will have to search for clues in other systems. Restoring from backup carries the risk of accidentally reinstating a compromised image. In this paper, we will describe common mistakes that experts make when responding to security incidents.

• A short excursion into WeChat;
• About the platform, the version of the application, the utilities used and the decryption of the executable file;
• • About two protocols (old one and new one);
• About serialization of objects;
• Used cryptography and key exchange;
• About headers and hash-functions;
• About the exposures found.

Hi there! A while ago, Positive Technologies published the news that ATMs manufactured by Diebold Nixdorf (previously known as Wincor), or more specifically, the RM3 and CMDv5 cash dispensers, contained a vulnerability which allowed attackers to withdraw cash and upload modified (vulnerable) firmware. And since my former colleague Alexei Stennikov and I were directly involved in finding this vulnerability, I would like to share some details.

Once I was asked to save a traffic dump of an Instagram app while viewing one particular user profile. Simply saving the traffic dump on the router didn't make sense because the app used TLS to communicate with the server. Existing solutions didn't work because they worked with an older version of Instagram.

Below I will describe how I managed to do it myself using mitmproxy, ghidra and frida.

GDB is THE debugger for Linux programs. It’s super powerful. But its user-friendliness or lack thereof can actually make you throw your PC out of the window. But what’s important to understand about GDB is that GDB is not simply a tool, it’s a debugging framework for you to build upon. In this article, I’m gonna walk you through GDB setup for reverse engineering and show you all of the necessary commands and shortcuts for your debugging workflow.

Reverse engineering might seem so complex, that not everyone has the bravery required to tackle it. But is it really that hard? Today we are gonna dive into the process of learning how to reverse engineer.

First of all, try to answer yourself, what are you hoping to achieve with reverse engineering? Because reverse engineering is a tool. And you should choose the right tool for your task. So when reverse engineering might be useful?

Where it all began

Most likely you've already heard about the famous exploit checkm8, which uses an unfixable vulnerability in the BootROM of most iDevices, including iPhone X. In this article, we'll provide a technical analysis of this exploit and figure out what causes the vulnerability.

Limit

Good day to you!

My name is Stanislav and I like to write code. This is my first english article on Habr which I made due to several reasons:

• Habr is now in English
• Lack of technical articles in the ReactOS hub
• Recent return of Geektimes to Habr
• Possibility of building ReactOS in ReactOS
• Quite interesting case of fixing the problem in ReactOS in which I was directly involved

This article is an english version of my very first article on russian.

Let me introduce the main figures in this story who actually fixed the bug preventing Git from running in ReactOS — the French developer Hermès Bélusca-Maïto (or just Hermes with hbelusca nickname) and of course me (with x86corez nickname).

The story begins with the following messages from the ReactOS Development IRC channel:

Jun 03 18:52:56 <hbelusca> Anybody want to work on some small problem? If so, can someone figure out why this problem https://jira.reactos.org/browse/CORE-12931 happens on ReactOS? :D
Jun 03 18:53:13 <hbelusca> That would help having a good ROS self-hosting system with git support.
Jun 03 18:53:34 <hbelusca> (the git assertion part only).

Introduction

If you have dabbled into microchip photographing before, then this article will probably not offer much to you. But if you want to get into it, but don’t know where to start, then it’s exactly for you.

Before we start, a fair warning: while the procedure is quite entertaining, at first it’ll probably be physically painful. The chemicals used during the process are toxic, so please handle them carefully – that way it’ll still hurt, but less so. Also, if you have even a slight amount of common sense, conduct the procedure in a fully-equipped chemical laboratory under supervision of trained professionals: we’ve had to deal with people who tried to do it at home immediately after reading the guide. And finally: if you don’t know whether you need to pour acid into water or water into acid without a Google search and don’t realize what this lack of knowledge will entail – stop reading this immediately and go to a chemistry 101 course in a local college or something.