New Malware Found Infecting Microsoft Teams Meetings

You may want to think twice the next time you’re on a conference call. It’s not really a time you can let your guard down. Even when doing something as innocuous as joining a chat with co-workers, you can still get hit with malware. Security experts discovered hackers have been targeting Microsoft Teams meetings with malware.

Security Firm Discovered Malware Attacks

It was email security firm Avanan that discovered the malware attack. Hackers find their way into Microsoft Teams meetings and leave behind infectious executable files.

Perhaps worse yet, this doesn’t seem to be an isolated incident. “Avanan has seen thousands of these attacks per month,” noted the company in a blog post.

It’s unclear how the hackers are gaining access to the Teams meetings. However, it’s assumed that unwitting employees are being targeted through their email accounts.

Once the hackers gain access to the email account, they use those credentials to get access to the work chat. It’s also possible that hackers are getting into the Teams meetings by stealing Microsoft 365 credentials via email phishing.

Avanan explained, “Given that hackers are quite adept at compromising Microsoft 365 accounts using traditional email phishing methods, they’ve learned that the same credentials work for Teams.”

Microsoft Teams Malware User Centric
User Centric Executable File

Once they have access to the Microsoft Teams meetings, hackers pretend they are sharing a program titled “User Centric.” After a call participant installs the file, they end up with a Trojan program that loads malicious DLL files that allow the hacker to infiltrate the PC.

Avanan added that “by attaching the file to a Teams attack, hackers have found a new way to easily target millions of users.”

Microsoft Teams Malware Install
User Centric Malware Demo

While Avanan showed a demo of the malware on a Windows 7 machine, it also admitted it could easily run on Windows 10 by just adding a “few extra lines of code.”

Microsoft Teams Became a Perfect Delivery Vehicle

This all works because the call participants are unsuspecting. “Most employees have been trained to second…