A security researcher has spotted five malicious ad blockers extension in the Google Chrome Store that had already been installed by at least 20 million users.
Unfortunately, malicious browser extensions are nothing new. They often have access to everything you do online and could allow its creators to steal any information victims enter into any website they visit, including passwords, web browsing history and credit card details.
Creators of these extensions also used popular keywords in their names and descriptions to rank top in the search results, increasing the possibility of getting more users to download them.
“All the extensions I’ve highlighted are simple rip-offs with a few lines of code and some analytics code added by the authors,” Meshkov says.
After Meshkov reported his findings to Google on Tuesday, the tech giant immediately removed all of the following mentioned malicious ad blockers extension from its Chrome Store:
- uBlock Plus (8 million+ users)
- [Fake] Adblock Pro (2 million+ users)
- HD for YouTube™ (400,000+ users)
- Webutation (30,000+ users)
The malicious extension then receives commands from the remote server, which are executed in the extension ‘background page’ and can change your browser’s behavior in any way.
“These commands are scripts which are then executed in the privileged context (extension’s background page) and can change your browser behavior in any way,” Meshkov says.
“Basically, this is a botnet composed of browsers infected with the fake Adblock extensions,” Meshkov says. “The browser will do whatever the command center server owner orders it to do.”
The researcher also analyzed other extensions on the Chrome Store and found four more extensions using similar tactics.
Since browser extension takes permission to access to all the web pages you visit, it can do practically anything.
So, you are advised to install as few extensions as possible and only from companies you trust.