> Dropping ntp packages > 128 bytes by default seems reasonable to me.

Yes and no. From the paranoid perspective of an IDS/firewall it's 
perfectly reasonable. From the inquisitive perspective of a student and 
research of NTP, it's a shame. It's really neat that you can ask an NTP 
server where it gets the time, what its software versions are, etc. It's 
a legitimate and useful feature of the product, and it's a shame that a 
seven year old exploit that's long since been patched means that a lot 
of people now block the requests.

On the other hand, if I were running an important server I'd block those 
requests too. The only real beef I have is that someone happened to see 
this report and file an abuse complaint with my ISP. Whose response, 
btw, was to threaten to terminate my server in 4 hours if I didn't 
answer their email. Yeah, problems there too.

In an ideal world the snort rule would be smarter. It wouldn't block any 
long NTP packets, just those that could have exploited the seven year 
old security hole. I don't know anything about snort or how hard that 
would be to do.d

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