I published the following diary on isc.sans.org: “The Crypto Miners Fight For CPU Cycles“: I found an interesting piece of Powershell code yesterday. The purpose is to download and execute a crypto miner but the code also implements a detection mechanism to find other miners, security tools or greedy processes
I published the following diary on isc.sans.org: “Example of ‘MouseOver’ Link in a Powerpoint File“: I really like Microsoft Office documents… They offer so many features that can be (ab)used to make them virtual bombs. Yesterday, I found a simple one but nicely prepared Powerpoint presentation: Payment_copy.ppsx (SHA256:7d6f3eb45c03a8c2fca4685e9f2d4e05c5fc564c3c81926a5305b6fa6808ac3f). It was still
I published the following diary on isc.sans.org: “Fileless Malicious PowerShell Sample“: Pastebin.com remains one of my favourite place for hunting. I’m searching for juicy content and report finding in a Splunk dashboard: Yesterday, I found an interesting pastie with a simple Windows CMD script… [Read more]
I published the following diary on isc.sans.org: “If you want something done right, do it yourself!“. Another day, another malicious document! I like to discover how the bad guys are creative to write new pieces of malicious code. Yesterday, I found another interesting sample. It’s always the same story, a
I published the following diary on isc.sans.org: “Keep An Eye on your Root Certificates“. A few times a year, we can read in the news that a rogue root certificate was installed without the user consent. The latest story that pops up in my mind is the Savitech audio drivers
I published the following diary on isc.sans.org: “Some Powershell Malicious Code“. Powershell is a great language that can interact at a low-level with Microsoft Windows. While hunting, I found a nice piece of Powershell code. After some deeper checks, it appeared that the code was not brand new but it
I published the following diary on isc.sans.org: “Malicious script dropping an executable signed by Avast?“. Yesterday, I found an interesting sample that I started to analyze… It reached my spam trap attached to an email in Portuguese with the subject: “Venho por meio desta solicitar orçamento dos produtos” (“I hereby
I published the following diary on isc.sans.org: “Diverting built-in features for the bad“. Sometimes you may find very small pieces of malicious code. Yesterday, I caught this very small Javascript sample with only 2 lines of code… [Read more]
Tracking users with privileged access is a critical task in your security policy (SANS Critical Security Control #12). If the key point is to restrict the number of “power users” to the lowest, it’s not always easy. Most of them will argue that they need administrator rights “to be able to
This topic is not brand new, there exists plenty of solutions to forward Windows event logs to Logstash (OSSEC, Snare or NXlog amongst many others). They perform a decent job to collect events on running systems but they need to deploy extra piece of software on the target operating systems. For a specific
