Multiple vulnerabilities were discovered in ntp, an implementation of the Network Time Protocol: CVE-2015-1798 When configured to use a symmetric key with an NTP peer, ntpd would accept packets without MAC as if they had a valid MAC. This could allow a remote attacker to bypass the packet authentication and send malicious packets without having to know the symmetric key. CVE-2015-1799 When peering with other NTP hosts using authenticated symmetric association, ntpd would update its internal state variables before the MAC of the NTP messages was validated. This could allow a remote attacker to cause a denial of service by impeding synchronization between NTP peers. Additionally, it was discovered that generating MD5 keys using ntp-keygen on big endian machines would either trigger an endless loop, or generate non-random keys.