The Wikimedia Foundation has issued a warning stating that if Wikipedia visitors are seeing ads on its webpages, then they are infected with malware.
As the site pointed out on Tuesday, Wikipedia is funded by more than a million donors, and will never run advertisements other than Wikipedia's typical fundraiser. Unfortunately, the company doesn't state how users are acquiring the malware or the damage that it can cause, only that injected ads are a symptom. One example Wikimedia discovered was a Google Chrome browser extension called "I want this."
"Ads injected in this manner may be confined to some sites, even just to Wikipedia, or they may show up on all sites you visit," the company said. "Browsing through a secure (HTTPS) connection (which you can automate using the HTTPS everywhere extension) may cause the ads to disappear, but will not fix the underlying problem."
"Criminals aren't shy of earning affiliate cash by injecting unwanted adverts into webpages or redirecting users to sites or search results that innocent users didn't mean to visit," Sophos stated in a separate report.
Wikimedia said that visitors should start the malware hunt by checking browser plugins and disable any add-ons and browser extensions that may be causing the problem. Naturally visitors are also recommended to use spyware/malware removal tools like Ad-Aware and Malwarebytes (or Spybot Search and Destroy).
Of course, the ad injections may not be from malware at all: it could be via the user's ISP too. "This is most likely the case with Internet cafes or 'free' wireless connections," Wikipedia said. "But rest assured: you won’t be seeing legitimate advertisements on Wikipedia. We’re here to distribute the sum of human knowledge to everyone on the planet — ad-free, forever."