The Versa Director GUI provides an option to customize the look and feel of the user interface. This option is only available for a user logged with Provider-Data-Center-Admin or Provider-Data-Center-System-Admin. (Tenant level users do not have this privilege). The “Change Favicon” (Favorite Icon) option can be mis-used to upload a malicious file ending with .png extension to masquerade as image file. This is possible only after a user with Provider-Data-Center-Admin or Provider-Data-Center-System-Admin has successfully authenticated and logged in.Severity: HIGHExploitation Status:Versa Networks is aware of one confirmed customer reported instance where this vulnerability was exploited because the Firewall guidelines which were published in 2015 & 2017 were not implemented by that customer. This non-implementation resulted in the bad actor being able to exploit this vulnerability without using the GUI. In our testing (not exhaustive, as not all numerical versions of major browsers were tested) the malicious file does not get executed on the client. There are reports of others based on backbone telemetry observations of a 3rd party provider, however these are unconfirmed to date.