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. See CiscoNTPDev for discussion of this topic.
ntp-4.2.8p15 was released on 23 June 2020. It addresses 1 medium-severity security issue in ntpd, and provides 13 non-security bugfixes over 4.2.8p13.
Are you using Autokey in production? If so, please contact Harlan - he's got some questions for you.
13.1. Cisco NTP
Almost all Cisco networking devices (routers, switches, firewalls, etc.) include an NTP implementation. Some routing protocols require synchronized time, and of course accurate time is needed for security logging purposes.
The Cisco implementation is based on The Reference NTP Implementation
, but has been modified to:
- run on the networking device hardware, which can be architecturally quite different from a general purpose server or workstation
- be configurable using Cisco management tools and configuration files
Routers and switches are not intended to be general purpose NTP servers.
There is no reference clock support built into Cisco's implementation; external servers must be configured.
Related topics: Cisco NTP pages