The calculated severity for Plugins has been updated to use CVSS v3 by default. Plugins that do not have a CVSS v3 score will fall back to CVSS v2 for calculating severity. Severity display preferences can be toggled in the settings dropdown.
The remote host is running a web browser.
The remote host is running the Amazon Silk web browser. The Amazon Silk web browser is a custom browser that only runs on the Amazon Kindle Fire tablet.