CVE-2016-1547

Name of the Vulnerable Software and Affected Versions NTP versions 4.2.8p4 and earlier NTPSec version a5fb34b9cc89b92a8fef2f459004865c93bb7f92

Description An off-path attacker can cause a preemptible client association to be demobilized by sending a crypto NAK packet to a victim client with a spoofed source address of an existing associated peer. This issue persists even when authentication is enabled.

Recommendations For NTP versions 4.2.8p4 and earlier, consider disabling the preemptible client association feature until a patch is available. For NTPSec version a5fb34b9cc89b92a8fef2f459004865c93bb7f92, restrict access to the crypto NAK packet handling mechanism to minimize the risk of exploitation. At the moment, there is no information about a newer version that contains a fix for this vulnerability.