Web Crawler Access Detection - Facebook

info Nessus Network Monitor Plugin ID 9180

Synopsis

Requests to this webserver indicate content was accessed by Facebook's URL checking service.

Description

Online content available through this server was recently linked to from Facebook. This can occur as a result of a shared post which includes the link, or sharing a link privately through a message within Facebook. This is an automated request from Facebook's servers to ensure the link is not deemed malicious and also attempts to preload an image or logo for the linked content. Within the client request headers, NNM has observed "facebookexternalhit/".

Solution

Evaluate whether the affected service or content should be externally accessible.

See Also

http://www.facebook.com/externalhit_uatext.php

https://en.wikipedia.org/wiki/Web_crawler

Plugin Details

Severity: Info

ID: 9180

Family: Generic

Published: 4/6/2016

Updated: 1/16/2019