[Dovecot] Would attempting plaintext auth repeatably cause a DOS and server to crash?

Daniel Reinhardt cryptodan at gmail.com
Fri Jun 21 10:42:29 EEST 2013

I doubt that the 1161 log lines would cause the VM to crash.  It would
potentially cause the logging directory to fill up if you have a small /var
partition where the logs are kept and at that point it could potentially
freeze the VM, but not cause the host to crash.  I think your issue
revolves around the storms.  I also do not consider a 1161 log lines a
DoS.  If it takes 1161 lines of failure entries to deny service to your
server, then I would take a look at your setup.

On Fri, Jun 21, 2013 at 3:37 AM, Steffen Kaiser <
skdovecot at smail.inf.fh-brs.de> wrote:

> Hash: SHA1
> On Fri, 21 Jun 2013, Hugh Davenport wrote:
>  and a minute later the server lost contact to the world. When I checked a
>> bit later,
>> the underlying host machine (dovecot runs on a VM (KVM)) had been powered
>> off.
> I cannot believe that a DoS of a guest VM causes the host machine to power
> off.
> - -- Steffen Kaiser
> Version: GnuPG v1.4.11 (GNU/Linux)
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Daniel Reinhardt
cryptodan at cryptodan.net

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