A flaw was found in the way NTP handled rate limiting. An attacker able to send a large number of crafted requests to an NTP server could trigger the rate limiting on that server, and prevent clients from getting a usable reply from the server. The default NTP configuration in Red Hat Enterprise Linux does not enable rate limiting. External References: https://www.cs.bu.edu/~goldbe/NTPattack.html http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-7705
