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QuantLoader - Malware Analysis


QuantLoader is a Trojan downloader that has been available for sale on underground forums for quite some time now. It has been used in campaigns serving a range of malware, including ransomware, Banking Trojans, and RATs. The campaign that we are going to analyze is serving a BackDoor.
In this post, we’ll take both a high-level look at the campaign flow, as well as a deep dive into how the malware executes, with a focus on the networking functions. We’ll dig into the binary to analyze how the malware executes and how it connects back to the C2. We’ll also analyze some interesting calls the malware makes, like calling and executing the netsh command to change local firewall rules.
The latest version of QuantLoader is being served through a phishing campaign using some interesting techniques. The campaign starts with a phishing email that comes with a link serving the victim the initial JS downloader. What’s interesting is that they’ve opted for a file:// (SMB) protocol rather than the traditional http://—maybe in order to get past some proxies/firewalls.
Read the full article on Malwarebytes Blog here.

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