[time-nuts] Time security musing - attacking the clock itself

[Hal Murray]

scmcgrath at gmail.com said:
> NTP servers. A way to hack them is to connect to one with a hostile server
> with higher stratum as NTP servers are configured as 'peers'    Without the
> md5 you can steer a server with md5 the servers just ignore the attacking
> server 

It's more complicated than that.

When I set up a NTP server, I tell it what servers to use.  If you just send 
my server a packet telling it a bogus time, your packet will get ignored.

If you control the network, you could intercept the packets I send to the 
servers I'm using and return forged packets.  You still have to get past 
various heuristics.  For example, ntpd won't step the clock by more than 1000 
seconds.


-- 
These are my opinions.  I hate spam.