Quote:A security firm said this week that it discovered PDF documents exploiting a Google Chrome browser zero-day. The vulnerability allowed attackers to collect data from users who opened PDF files inside Chrome's built-in PDF viewer.

Exploit detection service EdgeSpot, the company that found the files, says the PDF documents would contact a remote domain with information on the users' device --such as IP address, OS version, Chrome version, and the path of the PDF file on the user's computer.

This phone-home behavior did not take place when researchers opened the same PDF files in desktop PDF viewer apps, such as Adobe Reader and others, but was limited to Chrome only.

The company said it spotted two distinct sets of malicious PDF files exploiting this Chrome bug, with one series of files being circulated circa October 2017, and the second set in September 2018.