Privacy Filters should be applied to workstations handling restricted data, as well as to workstations located in publicly accessible areas and mobile devices used in remote/travel scenarios.
Control Type: Physical
Control Function: Preventive
Workstations that regularly view, process, and store data in the restricted or top secret categories should have the view of their screens obscured from casual onlookers/passersby. Privacy filters are a common physical security control designed to achieve this. They are thin, tinted sheets that attach to computer monitors, preventing passersby from seeing screen contents. Only the user sitting directly in front of the monitor can view the display. Limiting the viewing angle of screens helps mitigate the risk of shoulder surfing attacks. In addition to protecting sensitive information, privacy filters can provide other benefits, such as reducing blue light exposure.
Categories of employees who should be issued privacy filters include receptionists, finance and HR staff, and confidential resource advisors. Privacy filters also exist for laptop screens. If an organization has remote or traveling workers, it should consider issuing privacy filters to these employees to prevent shoulder surfing in busy areas like airports and coffee shops.