• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar
  • Skip to footer

My TechDecisions

  • Best of Tech Decisions
  • Topics
    • Video
    • Audio
    • Mobility
    • Unified Communications
    • IT Infrastructure
    • Network Security
    • Physical Security
    • Facility
    • Compliance
  • RFP Resources
  • Resources
  • Podcasts
  • Project of the Week
  • About Us
    SEARCH
IT Infrastructure, Network Security, News

Microsoft Warns of New Browser-Modifying Malware

Microsoft is warning about new malware that infects a device and adds browser extensions and changes settings to insert unauthorized ads into web pages.

December 11, 2020 Zachary Comeau Leave a Comment

Website Contact Form Malware

Microsoft is warning about a new malware strain that infects a user’s device and adds browser extensions and changes settings to insert unauthorized ads into web pages.

In a blog post, the Microsoft 365 Defender Research Team calls this family of browser-modification malware Adrozek. The malware has been infecting devices since at least May, and was observed on more than 30,000 devices at its peak in August.

It’s designed to inject adds into search engine results pages on multiple browsers, including Microsoft Edge, Google Chrome, Yandex Browser and Mozilla Firefox, according to Microsoft.

“We call this family of browser modifiers Adrozek,” the Microsoft Team wrote. “If not detected and blocked, Adrozek adds browser extensions, modifies a specific DLL per target browser, and changes browser settings to insert additional, unauthorized ads into web pages, often on top of legitimate ads from search engines.

“The intended effect is for users, searching for certain keywords, to inadvertently click on these malware-inserted ads, which lead to affiliated pages. The attackers earn through affiliate advertising programs, which pay by amount of traffic referred to sponsored affiliated pages.”

According to the Microsoft Team, browser modification malware aren’t necessarily new or all that advanced, but the fact that the malware can affect multiple browsers indicates a level of sophistication.

It also “maintains persistence and exfiltrates website credentials,” exposing users to additional risks if their device is infected.

Read Next: Microsoft: Cyberattacks On Healthcare Need To Stop

The Microsoft experts said they tracked 159 unique domains, each hosting an average of 17,300 unique URLs, which in turn host more than 15,300 unique, polymorphic malware samples on average.

From May to September, the team recorded hundreds of thousands of encounters of the malware across the globe, with heavy concentration in Europe and Asia.

The malware is installed through drive-by download, and attackers relied on polymorphism, allowing them to “churn huge volumes of samples as well as to evade detection.”

“While many of the domains hosted tens of thousands of URLs, a few had more than 100,000 unique URLs, with one hosting almost 250,000,” the Microsoft team said.

“This massive infrastructure reflects how determined the attackers are to keep this campaign operational.”

Some domains were up for just one day, while others were active for up to four months. Some of the domains distributed clean files in an attempt to evade detection.

Users who find this malware on their devices should reinstall their browsers, educate themselves on malware infections and use URL filtering solutions.

As always, users should also make sure their security software and operating systems are up to date. At the enterprise level, IT managers should reduce the attack surface by deploying application control to enforce the use of only authorized apps and services.

 

If you enjoyed this article and want to receive more valuable industry content like this, click here to sign up for our digital newsletters!

Related Content:

  • Cloud, SASE, Aryaka How the Cloud is Redefining Media Production and…
  • Singlewire Software mass notification interview Singlewire Software on Mass Notification Solutions
  • URI catchbox 1 Catchbox Plus: The Mic Solution That Finally Gave…
  • Engaging virtual meeting with diverse participants discussing creative ideas in a bright office space during daylight hours Diversified Survey: Workplace AV Tech is Falling Short,…

Free downloadable guide you may like:

  • Practical Design Guide for Office SpacesPractical Design Guide for Office Spaces

    Recent Gartner research shows that workers prefer to return to the office for in-person meetings for relevant milestones, as well as for face-to-face time with co-workers. When designing the office spaces — and meeting spaces in particular — enabling that connection between co-workers is crucial. But introducing the right collaboration technology in meeting spaces can […]

Reader Interactions

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Latest Downloads

Practical Design Guide for Office Spaces
Practical Design Guide for Office Spaces

Recent Gartner research shows that workers prefer to return to the office for in-person meetings for relevant milestones, as well as for face-to-fa...

New Camera Can Transform Your Live Production Workflow
New Camera System Can Transform Your Live Production Workflow

Sony's HXC-FZ90 studio camera system combines flexibility and exceptional image quality with entry-level pricing.

Creating Great User Experience and Ultimate Flexibility with Clickshare

Working and collaborating in any office environment today should be meaningful, as workers today go to office for very specific reasons. When desig...

View All Downloads

Would you like your latest project featured on TechDecisions as Project of the Week?

Apply Today!

More from Our Sister Publications

Get the latest news about AV integrators and Security installers from our sister publications:

Commercial IntegratorSecurity Sales

AV-iQ

Footer

TechDecisions

  • Home
  • Welcome to TechDecisions
  • Contact Us
  • Comment Guidelines
  • RSS Feeds
  • Twitter
  • Facebook
  • Linkedin

Free Technology Guides

FREE Downloadable resources from TechDecisions provide timely insight into the issues that IT, A/V, and Security end-users, managers, and decision makers are facing in commercial, corporate, education, institutional, and other vertical markets

View all Guides
TD Project of the Week

Get your latest project featured on TechDecisions Project of the Week. Submit your work once and it will be eligible for all upcoming weeks.

Enter Today!
Emerald Logo
ABOUTCAREERSAUTHORIZED SERVICE PROVIDERSYour Privacy ChoicesTERMS OF USEPRIVACY POLICY

© 2025 Emerald X, LLC. All rights reserved.