On Monday, November 6, 2006, 00:49:58, Matt wrote:
> I clearly stated that this violates the RFC, but there are 4 facts that
> you and others must understand.
>     1) RFC 821 (Simple Mail Transfer Protocol, circa 1982) which defines
>     this behavior was written 24 years ago.

Its  still  the  standard (with various extensions) which dictates how a
SMTP server should behave.

>     2) Regardless of how IMail currently behaves under these conditions,
>     Micrsoft and SmarterMail servers do behave this way, and most
>     servers have no issues with this behavior.

Its non standard.

>     3) It is a vulnerability to accept unlimited amounts of data by
>     SMTP, and the only way to stop this effectively is to not just stop
>     it mid-sream, but also respond to it midstream so that it doesn't
>     get respooled and resent.  Every IMail server will accept an E-mail
>     up to the capacity of the spool drive, but other servers like
>     Exchange and SmarterMail won't.

Any  MTA  is  free  to throw away the data whilst waiting for the end of
data indication.

>     4) The lack of support for RFC 1870 (SMTP Service Extension for
>     Message Size Declaration, circa 1995) only makes matters worse. 
>     Over 95% of the real-world issues would be resolved with proper
>     support for this.  This however wouldn't close the vulnerability on
>     it's own or resolve issues with standard/old-style SMTP connections.

No  disagreement  here, proper implementation of RFC 1870 whould be high
on the todo list.

>  ...
> If you have an alternative recommendation for closing the hole in the 
> RFC, please offer it up, but if you have no recommendation for how to 
> close this hole, please don't get in the way.

The  IETF accepts submissions from individuals.  If you feel so strongly
about  it  write  up  a  proposal for an extension to make an early DATA
response permissible.

-- 
[EMAIL PROTECTED]     "The avalanche has already started, it is too
Rod Dorman              late for the pebbles to vote." - Ambassador Kosh

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