ntp: missing check for zero originate timestamp

It was discovered that ntpd as a client did not correctly check the originate timestamp in received packets. A remote attacker could use this flaw to send a crafted packet to an ntpd client that would effectively disable synchronization with the server, or push arbitrary offset/delay measurements...

chrony: denial of service

CVE-2015-1853 denial of service: This issue is similiar to the "ntp CVE-2015-1799"-issue. An attacker knowing that NTP hosts A and B are peering with each other symmetric association can send a packet to host A with source address of B which will set the NTP state variables on A to the values sen...