Ntf · Ntp · CVE-2016-7434
**Name of the Vulnerable Software and Affected Versions**
NTP versions prior to 4.2.8p9
**Description**
The issue allows remote attackers to cause a denial of service (crash) via a crafted mrulist query. Multiple vulnerabilities could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition or modify the time being advertised by a device acting as a Network Time Protocol (NTP) server. These vulnerabilities include Network Time Protocol Trap Service Denial of Service, Network Time Protocol Broadcast Mode Denial of Service, Network Time Protocol Insufficient Resource Pool Denial of Service, Network Time Protocol Configuration Modification Denial of Service, Network Time Protocol mrulist Query Requests Denial of Service, Network Time Protocol Multiple Binds to the Same Port, and Network Time Protocol Rate Limiting Denial of Service.
**Recommendations**
For NTP versions prior to 4.2.8p9, update to version 4.2.8p9 or later to resolve the issue. As a temporary workaround, consider restricting access to the `read mru list` function until a patch is available. Additionally, workarounds that address one or more of these vulnerabilities may be available and are documented in the Cisco bug for each affected product.