9 posts in tag Reverse Engineering

Analyzing CVE-2015-0350 with REVEN

10 Dec 2018 by Luc - Technical - Reverse Engineering CVE CVE-2015-0350 Adobe Flash Reven

In this article we will show how we analyzed and tamper the PoC for CVE-2015-0350, an Adobe Flash vulnerability located in the parsing of JPEG-XR images, with the help of timeless analysis. With REVEN v1.5.0, from an input file causing a crash, we analyze the vulnerability by instantly time-traveling to...

Reversing DirtyC0W

10 Sep 2017 by Fred - Technical - Reverse Engineering Kernel Race-condition Reven

Everybody keeps in mind the Dirtyc0w Linux kernel bug. For those who don’t, take some time to refresh your memory here. The kernel race condition is triggered from user-space and can easily lead a random local user to write into any root owned file. In this article, we will demonstrate...

Unfolding obfuscated code with Reven (part 2)

25 Jan 2017 by tdta - Technical - Reverse Engineering Deobfuscation ctf Reven

Last time, by abstracting the runtime effect of the first virtual machine, we have reduced the challenge to a simpler but semantically equivalent program. Its control flow graph has a unique entry point as the basic block starting at 0x402048, whereas ones at 0x4023d4 and at 0x40266e are exit points...

Reversing Windows 7 BSoD display

04 Nov 2016 by Quentin - Technical - Axion BSoD Reverse Engineering Reven

In this post we’ll try to reverse Windows 7 BSoD using REVEN Axion in order to generate an image from memory and port accesses. Find which video mode is used As a first step, we will need to know which [video mode][wiki-output-caps] is used by the BSoD. To achieve this...

Unfolding obfuscated code with Reven (part 1, full write-up)

01 Nov 2016 by tdta - Technical - Reverse Engineering Deobfuscation ctf

In this article, we present a reverse engineering task performed using Reven. This is the full write-up corresponding to a first overview published in October. The binary examined here is F4b_XOR_W4kfu, the challenge scoring the highest number of points over all categories (cryptography, exploit, reverse engineering, etc.) in Grehack 2015’s...

Unfolding obfuscated code (part 1)

01 Oct 2016 by tdta, Fred, Mathieu, Benoit - Technical - Reverse Engineering Deobfuscation ctf Reven

This article is the first one in a series of two. We present an overview of some reverse engineering capabilities of REVEN-Axion, applied to a publicly available challenge, namely F4b_XOR_W4kfu, the most valued at Grehack 2015’s CTF contest (500 points). A more detailed write-up will be published soon for those interested....

IE crash analysis

17 Dec 2014 - Reven - Axion Reven taint Reverse Engineering use after free

Today we will analyse a crash of Internet Explorer. Reven scenario generation According to Exodus Intelligence, a vulnerability was silently fixed in MS13-055 patch along with other things. They showed on their blog how to exploit it. We generated our REVEN scenario where we give an html file to Internet...

Exploring text strings

21 Nov 2014 by Mathieu - Reven - Axion Reven Reverse Engineering

A program’s text strings often carry a lot of information, and are a basic although essential guide while analysing binaries. In this article we’ll see how REVEN handles and presents them. We’ll also see how one can automatically use this data to gain a better understanding a program’s behavior. The...

Following memory history with REVEN-Axion

14 Nov 2014 - Reven - Axion Reven Reverse Engineering

When working on traces of millions of instructions, one of the biggest challenges can be to detect the small portions of the code that are actually interesting. In this article, we have an application that reads from the network. We will show how to quickly find where the network frames...