In order to keep the community informed of threats against Wikimedia projects and users, the Wikimedia Security team has some information to share.
Malware installed via pirated contented downloaded from sites such as the Pirate Bay can cause web browsers compromised by the malware to create a fake donation banner for Wikipedia users. While the actual malware is not installed or distributed via Wikipedia, unaware visitors may be confused or tricked by it's activities.
The malware seeks to trick visitors to Wikipedia by looking like a legitimate Wikipedia banner asking for donations. Once the user clicks on the banner, they are then taken to a portal that leads them to transfer money to a fraudulent bitcoin account that is not controlled by the Foundation.
The current version of this malware is only infecting Microsoft Windows users at the time of this notification. To date, the number of people affected is small. The fraudulent accounts have taken approximately $700 from infected users. However, we strongly encourage all users to use and update their antivirus software.
Additional details and a screenshot of the fake donation banner on can be found at Bleepingcomputer.com.