Hi there,
This is not a virus, no.
The Internet Defense League is an organisation that works to ensure the way the internet works isn’t negatively impacted by laws that governments around the world make. You can see their website here:
https://www.internetdefenseleague.org/
Jetpack includes a widget that you can use to show support for the Internet Defense League, and you can also configure the widget to show special banners or messages on the site if there is a specific campaign active. Your screen shot shows such a banner.
You can control this widget’s settings from either the Customizer ->Widgets, or from Appearance Widgets, and you can find instructions on how this widget works here:
https://en.support.wordpress.com/widgets/internet-defense-league-widget/
