Envira Gallery Lite < 1.8.7.3 - Missing Authorization to Gallery Modification via envira_gallery_insert_images

Description

The plugin is vulnerable to unauthorized modification of data due to an improper capability check on the 'envira_gallery_insert_images' function in all versions up to, and including, 1.8.7.1. This makes it possible for authenticated attackers, with contributor access and above, to modify galleries on other users' posts.