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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: Echo
I'm not sure why this is such a worry since a lot of these responders have been working for over a decade, and they've all been just fine operating the way they are. -M On Fri, 16 Aug 2002, Brad Knowles wrote: > At 9:43 PM +0200 2002/08/16, Karsten W. Rohrbach wrote: > > > Brad Knowles([email protected])@2002.08.16 19:48:10 +0000: > >> What kinds of anti-abuse protection methods have people used for > >> "echo" accounts that they have set up? > > > > - scoreboard: one mail from one source addres in one minute time window > > Yeah, but then abusers could easily generate elephantine > quantities of messages, simply by randomly generating return > addresses (if they wanted to DoS you or your network), or by randomly > generating the user portion of return addresses (if they wanted to > abuse you to DoS someone else). If they know that there are multiple > domains handled by the same servers, they could randomly generate > addresses within that set of domains. > > > - gnupg: mail needs to be signed to fire a return mail. key of the > > signer must belong to the robot's gpg trust web. > > Ooh, so in order to use the echo server, they have to send a PGP > signed message? Wow, that's pretty expensive. That sounds like a > really excellent way to DoS your server. > > > Thanks for sharing! > > -- > Brad Knowles, <[email protected]> > > "They that can give up essential liberty to obtain a little temporary > safety deserve neither liberty nor safety." > -Benjamin Franklin, Historical Review of Pennsylvania. > > GCS/IT d+(-) s:+(++)>: a C++(+++)$ UMBSHI++++$ P+>++ L+ !E W+++(--) N+ !w--- > O- M++ V PS++(+++) PE- Y+(++) PGP>+++ t+(+++) 5++(+++) X++(+++) R+(+++) > tv+(+++) b+(++++) DI+(++++) D+(++) G+(++++) e++>++++ h--- r---(+++)* z(+++) >
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