NTP users are strongly urged to take immediate action to ensure that their NTP daemons are not susceptible to being used in distributed denial-of-service (DDoS) attacks. Please also take this opportunity to defeat denial-of-service attacks by implementing Ingress and Egress filtering through BCP38.
ntp-4.2.8p10was released on 21 March 2017. It addresses 6 medum- and 5 low-severity security issues, 4 informational security topics, 15 bugfixes, and contains other improvements over 4.2.8p9.
Please see the NTP Security Notice for vulnerability and mitigation details.Are you using Autokey in production? If so, please contact Harlan - he's got some questions for you.
ntpdis configured to enable mode 7 packets, and if the use of mode 7 packets is not properly protected thru the use of the available mode 7 authentication and restriction mechanisms, and if the (possibly spoofed) source IP address is allowed to send mode 7 queries, then an attacker can send a crafted packet to
ntpdthat will cause it to crash.
requestkeyto control who can issue mode 7 requests.
restrict noqueryto further limit mode 7 requests to trusted sources.