source: https://www.securityfocus.com/bid/26348/info

i-Gallery is prone to a remote information-disclosure vulnerability because it fails to properly sanitize user-supplied input.

Exploiting this issue may allow an unauthorized remote user to view arbitrary local files in the context of the webserver process. Information obtained may aid in further attacks.

i-Gallery 3.4 is vulnerable to this issue; other versions may also be vulnerable. 

http://www.example.com/gallery/igallery.asp?d=%5c../../%5c