From Discuss Scratch: https://scratch.mit.edu/discuss/topic/881911/ The ‘virus’ actually explained So, it's actually not a virus, but a vulnerability/exploit that has affected many Scratchers. It works by going into the project editor (or clicking ‘see inside’) and then going to the costume/backdrop editor. When you open it, the costumes can actually do Arbitrary Code Excecution, which is a way that code can be excecuted. In the desktop/offline editors, it's even worse because then they can run malicious shell programs and steal data from you! And this is not a theoretical possibility, it has already affected multiple Scratchers. What it can do It can delete and/or hack all projects, change the description of the victim's profile, comments things on the victim's profile without their concent and run malware (only on desktop/offline editors). How to prevent it Don't open suspicious projects asked by others to open and avoid any random links. If you did get hacked: Unshare all projects, change your password and delete any comments that you didn't type ASAP.
When I THINK ITS DISMISSABLE. I will remove this post and change the pinned post back to the easter egg. I am sorry if I myself have made copypasta on this. Kind regards.