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."

theft

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

READ MORE

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. ®

Similar topics


Other stories you might like

  • Prisons transcribe private phone calls with inmates using speech-to-text AI

    Plus: A drug designed by machine learning algorithms to treat liver disease reaches human clinical trials and more

    In brief Prisons around the US are installing AI speech-to-text models to automatically transcribe conversations with inmates during their phone calls.

    A series of contracts and emails from eight different states revealed how Verus, an AI application developed by LEO Technologies and based on a speech-to-text system offered by Amazon, was used to eavesdrop on prisoners’ phone calls.

    In a sales pitch, LEO’s CEO James Sexton told officials working for a jail in Cook County, Illinois, that one of its customers in Calhoun County, Alabama, uses the software to protect prisons from getting sued, according to an investigation by the Thomson Reuters Foundation.

    Continue reading
  • Battlefield 2042: Please don't be the death knell of the franchise, please don't be the death knell of the franchise

    Another terrible launch, but DICE is already working on improvements

    The RPG Greetings, traveller, and welcome back to The Register Plays Games, our monthly gaming column. Since the last edition on New World, we hit level cap and the "endgame". Around this time, item duping exploits became rife and every attempt Amazon Games made to fix it just broke something else. The post-level 60 "watermark" system for gear drops is also infuriating and tedious, but not something we were able to address in the column. So bear these things in mind if you were ever tempted. On that note, it's time to look at another newly released shit show – Battlefield 2042.

    I wanted to love Battlefield 2042, I really did. After the bum note of the first-person shooter (FPS) franchise's return to Second World War theatres with Battlefield V (2018), I stupidly assumed the next entry from EA-owned Swedish developer DICE would be a return to form. I was wrong.

    The multiplayer military FPS market is dominated by two forces: Activision's Call of Duty (COD) series and EA's Battlefield. Fans of each franchise are loyal to the point of zealotry with little crossover between player bases. Here's where I stand: COD jumped the shark with Modern Warfare 2 in 2009. It's flip-flopped from WW2 to present-day combat and back again, tried sci-fi, and even the Battle Royale trend with the free-to-play Call of Duty: Warzone (2020), which has been thoroughly ruined by hackers and developer inaction.

    Continue reading
  • American diplomats' iPhones reportedly compromised by NSO Group intrusion software

    Reuters claims nine State Department employees outside the US had their devices hacked

    The Apple iPhones of at least nine US State Department officials were compromised by an unidentified entity using NSO Group's Pegasus spyware, according to a report published Friday by Reuters.

    NSO Group in an email to The Register said it has blocked an unnamed customers' access to its system upon receiving an inquiry about the incident but has yet to confirm whether its software was involved.

    "Once the inquiry was received, and before any investigation under our compliance policy, we have decided to immediately terminate relevant customers’ access to the system, due to the severity of the allegations," an NSO spokesperson told The Register in an email. "To this point, we haven’t received any information nor the phone numbers, nor any indication that NSO’s tools were used in this case."

    Continue reading

Biting the hand that feeds IT © 1998–2021