Mutexes and malware analysis

There is many way to investigate malware and to “find evil” in an unknown executable. There will be situation where looking at a list of running processes won’t give you information to raise a red flag. You can always go deeper and perform more manual analysis. Even though this might be fun it might also be very time consuming…and we don’t always have the  luxury of time neither the resources.

Analysis of mutexes (sometime called mutant) can be a pretty good way to continue your analysis and find more evidence of “evil”.

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Indicator Of Compromise (IOC) – Part I

The release of the APT1 report from Mandiant has been one of the major recent event in the security world. I’m not going to review the report or to comment on it, even though the work that Mandiant did is really impressive and clearly demonstrate that governemental attacks are real. As I said in a previous post, cyber-espionage is on an increase trend and what Mandiant release is just the tip of the iceberg.

But what is really interesting in this report is the…appendix! Mandiant did include an awful lot of details such as FQDN, SSL Certificates and…Indicators of Compromise (e.g. IOC)! Let’s have a closer look at those IOCs. Continue reading “Indicator Of Compromise (IOC) – Part I”

Malware anti-VM technics

Malware analysis usually involved the use of virtual environment (VM) such as VMware, VirtualBox and plenty of other virtualisation solutions. Mentioning the main virtualisation product is great but such products are also used in sandbox and other testing environment such as Virustotal, Anubis, etc. There is a lot of reason for using a virtual environment for such analysis. In particular it give the ability to run malicious code in a control manner. You can customize your VM to meet your needs, install vulnerable software, change configuration, etc. Not to mention the ability to start from scratch and restore a previous snapshot. You can do it the “old” way by running the malicious executable directly on your operating system but you will take a little more risk not to mention the time you will lose to restore your system.

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Introduction to x86 Assembly Language – Part II

After the (very) high-level introduction of the part I, we are going to start to go a little bit deeper in the subject. Let’s start by having a closure look to the memory (RAM) and the related registers (e.g. general purpose registers, segment registers, EFLAGS and EIP). The goal is not to make a complete overview of how RAM is working, but keep in mind the overall objective: malware analysis. Therefore we won’t review everything and we will reduce the scope to x86 (32 bits) architectures (as it’s the most common architecture).

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Introduction to x86 Assembly Language – Part I

This article is an attempt to introduce some of the key concepts of x86 Assembly Language. It will focus on how such language is used by malware analyst to understand what a malicious software is doing and how it has been programmed by its author. Before going into more details, this article will explain some of the general concept and why assembly code is used to do malware analysis.

Continue reading “Introduction to x86 Assembly Language – Part I”

Cuckoo – Automated Malware Analysis

Cuckoo is a malware analysis system. Based on the description on the website:

Its goal is to provide you a way to automatically analyze files and collect comprehensive results describing and outlining what such files do while executed inside an isolated environment.

It’s mostly used to analyze Windows executables, DLL files, PDF documents, Office documents, PHP scripts, Python scripts, Internet URLs and almost anything else you can imagine.

But it can do much more…
It’s up to you to discover what and how.

Some of the results that Cuckoo generates are:

  • Trace of performed relevant win32 API calls
  • Dump of network traffic generated during analysis
  • Creation of screenshots taken during analysis
  • Dump of files created, deleted and downloaded by the malware during analysis
  • Trace of assembly instructions executed by malware process

In addition, Cuckoo allows you to:

  • Automate submission of analysis tasks
  • Create analysis packages to define custom operations and procedures for performing an analysis
  • Run multiple virtual machines concurrently
  • Script the process and correlation of analysis results data
  • Script and automate the generation of reports in the format you prefer

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Flame – Cyberwar in action?

Information about the Flame virus have been published in the the last few days of May 2012. This discovery has been made two years after Stuxnet (June 2010) and less than a year after Duqu (Sept. 2011). Despite the fact that those three virus have different objectives, they have in common their complexity and the fact that they have been probably developed by people with “unlimited” resources. So where are we now? Is this cyberwar? or this is the natural evolution of cyber criminal?

What is Flame? How does it work?

Easy question, but difficult answer! In short Flame is a little bit of everything. The best way to describe it to use the term “attack toolkit”. It’s a toolkit because it’s modular approach allow him to become a backdoor, a worm, it can also perform various malicious activities such as key logger, network sniffing, listening to audio interface, steal information, enable Bluetooth and scan other devices, etc. In short it can do more or less everything a hacker will dream of. Also, based on the experience of the security industry with Stuxnet everybody was expecting several Zero-Day attacks. There is actually no evidence of such type of attack in Flame. Especially there is still some questions about the initial infection vector. However Kaspersky has observed that a fully patched Windows 7 was still being infected, raising more suspicion about a zero day attack. Further analysis highlight a different story… Continue reading “Flame – Cyberwar in action?”