Gentoo Linux Security Advisory 201607-15 - Multiple vulnerabilities have been found in NTP, the worst of which could lead to Denial of Service. Versions less than 4.2.8_p8 are affected.
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Slackware Security Advisory - New ntp packages are available for Slackware 13.0, 13.1, 13.37, 14.0, 14.1, and -current to fix security issues.
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FreeBSD Security Advisory - Crypto-NAK packets can be used to cause ntpd(8) to accept time from an unauthenticated ephemeral symmetric peer by bypassing the authentication required to mobilize peer associations. FreeBSD 9.3 and 10.1 are not affected. Various other issues have also been addressed.
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Cisco Security Advisory - 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.
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