Scientific Linux Security Update : ntp on SL6.x, SL7.x i386/x86_64
Medium Nessus Plugin ID 86615
SynopsisThe remote Scientific Linux host is missing one or more security updates.
DescriptionIt was discovered that ntpd as a client did not correctly check timestamps in Kiss-of-Death packets. A remote attacker could use this flaw to send a crafted Kiss-of-Death packet to an ntpd client that would increase the client's polling interval value, and effectively disable synchronization with the server. (CVE-2015-7704)
It was found that ntpd did not correctly implement the threshold limitation for the '-g' option, which is used to set the time without any restrictions. A man-in-the-middle attacker able to intercept NTP traffic between a connecting client and an NTP server could use this flaw to force that client to make multiple steps larger than the panic threshold, effectively changing the time to an arbitrary value.
After installing the update, the ntpd daemon will restart automatically.
SolutionUpdate the affected packages.