Security considerations with using an NTP server

"Paper written for GIAC qualification with in depth analysis of NTP security.

An overview of NTP that's a little less verbose.

NTP is therefore vulnerable to security threats, whether from a malicious hacker who wants to alter the timestamp to commit fraud or a DDoS attack (Distributed Denial of Service - normally caused by malicious malware that floods a server with traffic) that blocks server access.

With regards to the pool servers, please remember they're volunteered servers.

From what I've read in the past, unless you have time critical tasks the highest risk is DDOS."