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-4.2.8p15was released on 23 June 2020. It addresses 1 medium-severity security issue in ntpd, and provides 13 non-security bugfixes over 4.2.8p13.
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.
ntpdccan be used to store and retrieve information in
ntpd. It is possible to store a data value that is larger than the size of the buffer that the
ntpduses to report the return value. If the length of the requested data value returned by
ctl_getitem()is too large, the value
NULLis returned instead. There are 2 cases where the return value from
ctl_getitem()was not directly checked to make sure it's not
NULL, but there are subsequent
INSIST()checks that make sure the return value is not
NULL. There are no data values ordinarily stored in
ntpdthat would exceed this buffer length. But if one has permission to store values and one stores a value that is "too large", then
ntpdwill abort if an attempt is made to read that oversized value.