Malwarebytes vs Firefox prefs file
Every time Malwarebytes 4.0 runs a scan on my PC it flags my Firefox prefs.js file as containing a PUP.Optional.Conduit. I presume this is linked to some add-on, but how can I find out which? And should I remove it? Jonathan Glassier
PUP.Optional.Conduit refers to an online platform used to create custom toolbars and apps. It’s known to change browser settings and display potentially dangerous adverts. However, it’s not actually malware, so don’t panic. Start by making sure that Firefox is closed before instructing Malwarebytes to quarantine the file – this will ensure the file is actually removed. Firefox will then recreate a new prefs.js file. If the file keeps getting flagged, you’ll need to browse to your Firefox profile folder (press Win-R, type %appdata%\Mozilla\Firefox\ Profiles\ and hit [Enter], then double-click the folder ending in ‘.default’). Right-click prefs.js and choose Edit to open it in
Notepad to see if you can easily locate any suspicious-looking entries. If you can link them to a specific add-on (including any search engines you may have added), try removing it to see if that removes the entry and resolves the problem – do so via about:addons (for extensions) and Options > Search (for search engines). If you can’t find the culprit, but you’re happy with your current setup, then PUP. Optional.Conduit is more an irritation than a genuine threat, so consider just ignoring it.
Carrie Marshall