Web Crawler Access Detection - Facebook
Info Nessus Network Monitor Plugin ID 9180
SynopsisRequests to this webserver indicate content was accessed by Facebook's URL checking service.
DescriptionOnline 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, PVS has observed "facebookexternalhit/".
SolutionEvaluate whether the affected service or content should be externally accessible.