Cyber Resilience – Microsoft Will Begin Blocking Dangerous Extensions in OneNote
As WaterISAC has reported multiple times since January, threat actors made a significant pivot to abusing OneNote to spread malware after Microsoft automatically blocked macros last year. Due to this surge in activity, Microsoft has announced they will begin blocking files within OneNote that contain dangerous extensions, similar to Outlook, Word, Excel, and PowerPoint. Microsoft has included 120 file types/extensions along with the capability to block additional extensions if needed.