51l3nc3, a member of the AXIS OS Bug Bounty Program, has found that the VAPIX API uploadoverlayimage.cgi did not have sufficient input validation to allow an attacker to upload files to block access to create image overlays in the web interface of the Axis device.
The product receives input that is expected to be of a certain type, but it does not validate or incorrectly validates that the input is actually of the expected type.