I published the following diary on isc.sans.edu: “Collecting IOCs from IMAP Folder“: I’ve plenty of subscriptions to “cyber security” mailing lists that generate a lot of traffic. Even if we try to get rid of emails, that’s a fact: email remains a key communication channel. Some mailing lists posts contain
I published the following diary on isc.sans.edu: “Powershell Payload Stored in a PSCredential Object“: An interesting obfuscation technique to store a malicious payload in a PowerShell script: In a PSCredential object! The PSCredential class can be used to manage credentials in a centralized way. Just have a look at this example. First, let’s encrypt
I published the following diary on isc.sans.edu: “Malicious Excel With a Strong Obfuscation and Sandbox Evasion“: For a few weeks, we see a bunch of Excel documents spread in the wild with Macro V4. But VBA macros remain a classic way to drop the next stage of the attack on the
The popular web conference platform Zoom has been in the storm for a few weeks. With the COVID19 pandemic, more and more people are working from home and the demand for web conference tools has been growing. Vulnerabilities have been discovered in the Zoom client and, based on the fact
I published the following diary on isc.sans.edu: “Weaponized RTF Document Generator & Mailer in PowerShell“: Another piece of malicious PowerShell script that I found while hunting. Like many malicious activities that occur in those days, it is related to the COVID19 pandemic. Its purpose of simple: It checks if Outlook
I published the following diary on isc.sans.edu: “PowerShell Sample Extracting Payload From SSL“: Another diary, another technique to fetch a malicious payload and execute it on the victim host. I spotted this piece of Powershell code this morning while reviewing my hunting results. It implements a very interesting technique. As usual,
One of my sources of threat intelligence is a bunch of honeypots that I’m operating here and there. They are facing the wild Internet and, as you can imagine, they get hit by many “attackers”. But are they really bad people? Of course, the Internet is full of bots tracking
Bad guys are always trying to use “exotic” file extensions to deliver their malicious payloads. If common dangerous extensions are often blocked by mail security gateways, there exists plenty of less common extensions. These days, with the COVID19 pandemic, we are facing a peak of phishing and scams trying to
I published the following diary on isc.sans.edu: “Obfuscated with a Simple 0x0A“: With the current Coronavirus pandemic, we continue to see more and more malicious activity around this topic. Today, we got a report from a reader who found a nice malicious Word document part of a Coronavirus phishing campaign. I
I published the following diary on isc.sans.edu: “Malicious JavaScript Dropping Payload in the Registry“: When we speak about “fileless” malware, it means that the malware does not use the standard filesystem to store temporary files or payloads. But they need to write data somewhere in the system for persistence or
