CVE-2016-4955

ntpd en NTP 4.x en versiones anteriores a 4.2.8p8, cuando está habilitada la autoclave, permite a atacantes remotos provocar una denegación de servicio (limpiando el par variable y corte de asociación) enviando (1) un paquete crypto-NAK manipulado o (2) un paquete con un valor MAC incorrecto en un momento determinado.

Aanchal Malhotra discovered that NTP incorrectly handled authenticated broadcast mode. A remote attacker could use this issue to perform a replay attack. Matt Street discovered that NTP incorrectly verified peer associations of symmetric keys. A remote attacker could use this issue to perform an impersonation attack. Jonathan Gardner discovered that the NTP ntpq utility incorrectly handled memory. An attacker could possibly use this issue to cause ntpq to crash, resulting in a denial of service. This issue only affected Ubuntu 16.04 LTS. Various other issues were also addressed.