CVE-2015-7692

La función crypto_xmit en ntpd en NTP 4.2.x en versiones anteriores a 4.2.8p4, y 4.3.x en versiones anteriores a 4.3.77 permite que atacantes remotos provoquen una denegación de servicio. NOTA: esta vulnerabilidad existe debido a una solución incompleta para CVE-2014-9750.

It was found that the fix for CVE-2014-9750 was incomplete: three issues were found in the value length checks in NTP's ntp_crypto.c, where a packet with particular autokey operations that contained malicious data was not always being completely validated. A remote attacker could use a specially crafted NTP packet to crash ntpd.

Multiple Cisco products incorporate a version of the ntpd package. Versions of this package are affected by one or more vulnerabilities that could allow an unauthenticated, remote attacker to create a denial of service (DoS) condition or modify the time being advertised by a device acting as a network time protocol (NTP) server. On October 21st, 2015, NTP.org released a security advisory detailing 13 issues regarding multiple DoS vulnerabilities, information disclosure vulnerabilities, and logic issues that may result in an attacker gaining the ability to modify an NTP server's advertised time.