WordPress Photo Gallery Plugin <= 1.8.21 Stored Cross Site Scripting in UploadHandler

The image upload component allows SVG files and the regular expression used to remove script tags can be bypassed by using a Cross Site Scripting payload which does not match the regular expression; one example of this is the inclusion of whitespace within the script tag. An attacker must target an authenticated user with permissions to access this feature, however once uploaded the payload is also accessible to unauthenticated users.