Ad-scamming, login-stealing Windows malware is hitting Chrome, Edge, Firefox, Yandex browsers, says Microsoft

Sophisticated campaign has been going on for months, we're told

On Thursday Microsoft warned that there's an ongoing campaign to distribute malware that modifies web browsers to conduct credential theft and ad fraud.

Since at least May, 2020, unidentified cybercriminals have been distributing a family of browser modifiers dubbed Adrozek, Microsoft said. The code, which targets Google Chrome, Microsoft Edge, Mozilla Firefox, and Yandex Browser on Windows, mainly injects ads into search results pages.

"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 Microsoft 365 Defender Research Team said its blog post.

"The intended effect is for users, searching for certain keywords, to inadvertently click on these malware-inserted ads, which lead to affiliated pages."


Chrome extensions are 'the new rootkit' say researchers linking surveillance campaign to Israeli registrar Galcomm


The attackers make their money through participation in advertising affiliate programs, which pay for the online traffic referred to specific web pages. To date, these ads don't appear to point to sites hosting other malware, but Microsoft suggests that could change at any time.

In Firefox, Adrozek also scans the victim's device for stored user credentials and sends what it finds to the attacker.

Such attacks and tactics have been seen before, but according to Microsoft, the scale and complexity of the campaign, targeting multiple browsers via distributed infrastructure, shows cybercriminals becoming more sophisticated in their efforts.

Microsoft said it has detected 159 unique domains, each hosting an average of 17,300 unique URLS that each host more than 15,300 unique, polymorphic malware samples on average. Its systems measured hundreds of thousands of contacts with Adrozek malware, mainly in Europe, South Asia, and Southeast Asia. And the campaign is ongoing.

This distribution system offers up software for download that unwitting victims run. The installer drops a randomly named .exe file that installs a primary payload disguised as legitimate audio software in the Windows Program Files folder. The installed code then makes changes to various browser components and settings to enable ad injection and credential theft.

Adrozek also attempts to alter browser DLLs, such as MsEdge.dll in Microsoft Edge so changes to the Secure Preferences file won't be noticed. In Chromium-based browsers, it modifies a security-related hash integrity check used to prevent tampering. It also adds a policy to prevent the browsers it subverts from being updated.

Microsoft says that its Defender Antivirus, which ships with Windows 10, can defend against Adrozek. And it advises those who find the malware on their system to reinstall their browser. ®

Broader topics

Other stories you might like

  • Robotics and 5G to spur growth of SoC industry – report
    Big OEMs hogging production and COVID causing supply issues

    The system-on-chip (SoC) side of the semiconductor industry is poised for growth between now and 2026, when it's predicted to be worth $6.85 billion, according to an analyst's report. 

    Chances are good that there's an SoC-powered device within arm's reach of you: the tiny integrated circuits contain everything needed for a basic computer, leading to their proliferation in mobile, IoT and smart devices. 

    The report predicting the growth comes from advisory biz Technavio, which looked at a long list of companies in the SoC market. Vendors it analyzed include Apple, Broadcom, Intel, Nvidia, TSMC, Toshiba, and more. The company predicts that much of the growth between now and 2026 will stem primarily from robotics and 5G. 

    Continue reading
  • Deepfake attacks can easily trick live facial recognition systems online
    Plus: Next PyTorch release will support Apple GPUs so devs can train neural networks on their own laptops

    In brief Miscreants can easily steal someone else's identity by tricking live facial recognition software using deepfakes, according to a new report.

    Sensity AI, a startup focused on tackling identity fraud, carried out a series of pretend attacks. Engineers scanned the image of someone from an ID card, and mapped their likeness onto another person's face. Sensity then tested whether they could breach live facial recognition systems by tricking them into believing the pretend attacker is a real user.

    So-called "liveness tests" try to authenticate identities in real-time, relying on images or video streams from cameras like face recognition used to unlock mobile phones, for example. Nine out of ten vendors failed Sensity's live deepfake attacks.

    Continue reading
  • Lonestar plans to put datacenters in the Moon's lava tubes
    How? Founder tells The Register 'Robots… lots of robots'

    Imagine a future where racks of computer servers hum quietly in darkness below the surface of the Moon.

    Here is where some of the most important data is stored, to be left untouched for as long as can be. The idea sounds like something from science-fiction, but one startup that recently emerged from stealth is trying to turn it into a reality. Lonestar Data Holdings has a unique mission unlike any other cloud provider: to build datacenters on the Moon backing up the world's data.

    "It's inconceivable to me that we are keeping our most precious assets, our knowledge and our data, on Earth, where we're setting off bombs and burning things," Christopher Stott, founder and CEO of Lonestar, told The Register. "We need to put our assets in place off our planet, where we can keep it safe."

    Continue reading

Biting the hand that feeds IT © 1998–2022