Category: Lab Notes

As we have noted before, attackers will leverage any file format they can to evade security protections put in place by their targets. (https://cofenselabs.com/all-you-need-is-text/).

On Jun 11, 2020 we noticed an odd file extension show up in our analysis pipeline.

It was a jnlp file. The jnlp extension is short …

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While working on some wrapper scripts for dumping OLE VBA macros and attempting to deobfuscate them in search of downloader links, I came across an annoying, but not new, edge case – VBA macros using Excel cells to store additional code. In the past I used Philippe Lagadec’s excellent ViperMonkey

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Normally we try to allow our personalities shine through our posts, but we are living in abnormal times. The coronavirus (COVID-19) is a pandemic and is affecting everyone and everything.  As if worrying about whether or not you will live or die isn’t enough, criminals began capitalizing on the worry …

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While searching through our data for any samples of our current pandemic and threat actors’ favorite theme, I came across a rather interesting sample. The email and DOC are rather simple but consistent in theme and lacking the usual spelling and grammatical errors.

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An Easy Networking Lab

We tend to go a bit overkill on everything. Building a desktop? Yeah, 64GB of RAM should suffice, you know, just in case Windows 11 comes out next week. Testing a new service in Amazon EC2? Well t3.xlarge has more than enough just enough in case of technical things I …

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All You Need Is Text

Recently I decided to go spelunking through our data in search of any rarities that we have collected. And today I will share some of these interesting specimens. None of these samples are truly unique and most of them are already well known and well documented, but this exercise can …

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Yes… another Emotet post, but they just keep on changing things up! We were having a look around our data from the Emotet botnet and came across an interesting example of the reply-chain tactic that has become the new normal for them.

As can be seen in the example above, …

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Shotgun Wedding

An email caught my eye this morning. Not because of a unique social engineering theme or a new delivery technique, but because of the sheer number of attachments, a shotgun approach to malware delivery. There were 3 RTF files with spoofed .doc and docx.doc extensions, an ARJ archive containing an …

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