218. Adversaries Abuse .Desktop Files to Attack Linux Systems

Hello everyone!

Using phishing emails to obtain the initial access to a Windows host is quite common technique. And we see such emails every day. But what about Linux? Let's look at an example!

According to this report, APT36 leveraged malicious .desktop files to deliver Poseidon - a Mythic agent. These files were masqueraded to look like PDF documents, for example,  Document Details.pdf.desktop. In fact, such files are just shortcut files, but for Linux.

So, if you have Linux workstations, it's a good idea to hunt for suspicious .desktop files:

event_type: "processcreatenix"

AND

cmdline.keyword: /.*\.desktop\s.*/

See you tomorrow!

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