Latest QBot Attacks Use a Mixture of PDF Attachments and Windows Scripting Host Files to Infect Victims

QBot Attacks Uses PDF Attachments and Windows Scripting Host FilesQBot malware seems to be outliving its competitors through innovative new ways to socially engineer victims into helping install it.

Because “good guys” are constantly updating the way they detect attacks, cybercriminals need to run at an equally fast pace, coming up with new ways to see malware installed on victim endpoints. What determines the longevity of a piece of malware really comes down to whether its authors are working to stay ahead of security solutions.

This appears to be the case with Qbot. Since 2008, we’ve seen QBot in the past using a wide variety of tactics, including HTML Smuggling, and it continues to be a formidable foe, with its latest iteration using several tactics together.

First, it uses an HTML attachment made to appear as if it’s a PDF file. The HTML downloads and opens a PDF that asks the user to click the "OPEN" button to reveal the “protected file."


This user interaction is the key. The clicking of the button causes a ZIP file that contains a Windows scripting host file (WSF file) to launch. The ZIP file helps obfuscate the malicious intent of the scripting file from security solutions.

The script installs QBot onto the endpoint.

As I mentioned, the interaction by the user is the key – to this and every phishing attack other than response-based attacks (where the attacks are purely social engineering). By training users through security awareness training to not interact with emails they are unsure of, organizations can significantly reduce the risk of a successful cyber attack.

BleepingComputer has the story.

Subscribe to Our Blog

Comprehensive Anti-Phishing Guide

Get the latest about social engineering

Subscribe to CyberheistNews