I published the following diary on isc.sans.edu: “Malicious PowerShell Targeting Cryptocurrency Browser Extensions“: While hunting, I found an interesting PowerShell script. After a quick check, my first conclusion was that it is again a simple info stealer. After reading the code more carefully, the conclusion was different: It targets crypto-currency browser
I published the following diary on isc.sans.edu: “Simple Powershell Ransomware Creating a 7Z Archive of your Files“: If some ransomware families are based on PE files with complex features, it’s easy to write quick-and-dirty ransomware in other languages like Powershell. I found this sample while hunting. I’m pretty confident that this
I published the following diary on isc.sans.edu: “Did You Spot “Invoke-Expression”?“: When a PowerShell script is obfuscated, the deobfuscation process is, most of the time, performed through the Invoke-Expression cmdlet. Invoke-Expression evaluates the string passed as an argument and returns the results of the commands inside the string… [Read more]
I published the following diary on isc.sans.edu: “PowerShell Backdoor Launched from a ShellCode“: When you need to perform malicious actions on a victim’s computer, the Internet is full of resources that can be reused, forked, slightly changed to meet your requirements. After all, why reinvent the wheel if some pieces
I published the following diary on isc.sans.edu: “Party in Ibiza with PowerShell“: Today, I would like to talk about PowerShell ISE or “Integration Scripting Environment”. This tool is installed by default on all Windows computers (besides the classic PowerShell interpreter). From a malware analysis point of view, ISE offers a key feature:
I published the following diary on isc.sans.edu: “Restricting PowerShell Capabilities with NetSh“: The Christmas break is coming for most of us, let’s take some time to share some tips to better protect our computers. The Microsoft Windows OS has plenty of tools that, when properly used, can reduce risks to be
I published the following diary on isc.sans.edu: “Basic Obfuscation With Permissive Languages”: For attackers, obfuscation is key to keep their malicious code below the radar. Code is obfuscated for two main reasons: defeat automatic detection by AV solutions or tools like YARA (which still rely mainly on signatures) and make the code
I published the following diary on isc.sans.edu: “Malicious Powershell Script Dissection”: Here is another example of malicious Powershell script found while hunting. Such scripts remain a common attack vector and many of them can be easily detected just by looking for some specific strings. Here is an example of YARA
I published the following diary on isc.sans.edu: “Dissecting Malicious Office Documents with Linux”: A few months ago, Rob wrote a nice diary to explain how to dissect a (malicious) Office document (.docx). The approach was to use the OpenXML SDK with Powershell. This is nice but how to achieve the
I published the following diary on isc.sans.edu: “Malicious PowerShell Compiling C# Code on the Fly“: What I like when hunting is to discover how attackers are creative to find new ways to infect their victim’s computers. I came across a Powershell sample that looked new and interesting to me. First,
