[ntp:security] [Bug 3042] Broadcast interleave

bugzilla-daemon at ntp.org bugzilla-daemon at ntp.org
Thu May 5 12:13:18 UTC 2016


--- Comment #3 from Miroslav Lichvar <mlichvar at redhat.com> 2016-05-05 12:13:18 UTC ---
In a network with broadcast clients not using interleaved mode an attacker can
send a broadcast packet with spoofed source address and non-zero origin
timestamp, which will enable the broadcast interleaved mode on clients. Clients
will then process packets from the real server in wrong mode and won't be able
to synchronize. This happens even when authentication is enabled.

The interleaved mode should be enabled only when the authentication check
passed. When authentication is not enabled, it would be nice if the client was
at least able to switch back to non-interleaved mode when a packet with zero
origin timestamp is received.

Configure bugmail: http://bugs.ntp.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are on the CC list for the bug.

More information about the security mailing list