FreeBSD : ntpd DRDoS / Amplification Attack using ntpdc monlist command (3d95c9a7-7d5c-11e3-a8c1-206a8a720317)
Medium Nessus Plugin ID 71960
SynopsisThe remote FreeBSD host is missing a security-related update.
Descriptionntp.org reports :
Unrestricted access to the monlist feature in ntp_request.c in ntpd in NTP before 4.2.7p26 allows remote attackers to cause a denial of service (traffic amplification) via forged (1) REQ_MON_GETLIST or (2) REQ_MON_GETLIST_1 requests, as exploited in the wild in December 2013
Use noquery to your default restrictions to block all status queries.
Use disable monitor to disable the ``ntpdc -c monlist'' command while still allowing other status queries.
SolutionUpdate the affected package.