YSK that the popular program Notepad++ was recently compromised by hackers
Why YSK: This program is widely used and even on many critical systems for businesses and other organizations. Its update process was compromised and provided access to state sponsored hackers.
If you have this program, you should uninstall it and install the most recent version from the website on all machines that have it. Critical systems should be thoroughly inspected to ensure that outside actors do not have access.