Mozilla temporarily added the dangerous Microsoft.NET Framework Assistant add-on to its blacklist over the weekend, a move that effectively disabled the dangerous extension and plug-in for all Firefox users. The move came in the wake of an admission from Microsoft that the extension was exposing users to drive-by malware downloads via a remote code execution vulnerability. Mozilla VP of engineering Mike Shaver explains why the move was made. After some clarifications from Redmond, the add-in was unblocked. Mozilla has used its blocklist mechanism to kill problematic extensions.
Source: https://threatpost.com/mozilla-temporarily-blocklists-ms-firefox-add-101909/72342/