I published the following diary on isc.sans.org: “Analysis of a Maldoc with Multiple Layers of Obfuscation“. Thanks to our readers, we get often interesting samples to analyze. This time, Frederick sent us a malicious Microsoft Word document called “Invoice_6083.doc” (which was delivered in a zip archive). I had a quick
Category: Malware
[SANS ISC] Hunting for Malicious Excel Sheets
I published the following diary on isc.sans.org: “Hunting for Malicious Excel Sheets“. Recently, I found a malicious Excel sheet which contained a VBA macro. One particularity of this file was that useful information was stored in cells. The VBA macro read and used them to download the malicious PE file.
[SANS ISC] Diverting built-in features for the bad
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]
[SANS ISC Diary] Example of Multiple Stages Dropper
I published the following diary on isc.sans.org: “Example of Multiple Stages Dropper“. If some malware samples remain simple (see my previous diary), others try to install malicious files in a smooth way to the victim computers. Here is a nice example that my spam trap captured a few days ago. The
[SANS ISC Diary] Not All Malware Samples Are Complex
I published the following diary on isc.sans.org: “Not All Malware Samples Are Complex“. Everyday we hear about new pieces of malware which implement new techniques to hide themselves and defeat analysts. But they are still people who write simple code that just “do the job”. The sample that I’m reviewing today had a very
[SANS ISC Diary] Many Malware Samples Found on Pastebin
I published the following diary on isc.sans.org: “Many Malware Samples Found on Pastebin“. pastebin.com is a wonderful website. I’m scrapping all posted pasties (not only from pastebin.com) and pass them to a bunch of regular expressions. As I said in a previous diary, it is a good way to perform
Quick Integration of MISP and Cuckoo
With the number of attacks that we are facing today, defenders are looking for more and more IOC’s (“Indicator of Compromise) to feed their security solutions (firewalls, IDS, …). It becomes impossible to manage all those IOC’s manually and automation is the key. There are two main problems with this
[SANS ISC Diary] Malicious SVG Files in the Wild
I published the following diary on isc.sans.org: “Malicious SVG Files in the Wild“. In November 2016, the Facebook messenger application was used to deliver malicious SVG files to people [1]. SVG files (or “Scalable Vector Graphics”) are vector images that can be displayed in most modern browsers (natively or via
Using Monitor Resolution as Obfuscation Technique
A quick blog post about a malicious VBScript macro that I analysed… Bad guys have always plenty of ideas to obfuscate their code. The macro was delivered via a classic phishing email with an attached zip archive that contained a Windows .lnk file. The link containing a simple call to
[SANS ISC Diary] Another Day, Another Malicious Behaviour
I published the following diary on isc.sans.org: “Another Day, Another Malicious Behaviour“. Every day, we are spammed with thousands of malicious emails and attackers always try to find new ways to bypass the security controls. Yesterday, I detected a suspicious HTTP GET request: … [Read more]