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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">As my objective on the utilization of syslog-ng is the authentication and certification of received security and auditing events, I implemented an internal CA which generates a certificate per syslog-ng client.<o:p></o:p></p>
<p class="MsoNormal">Once there was someone that misconfigured a client and got a certificate for a different client. The funny part of it is that no one observed any problem as the certificate, which was generated for a client having an ip (different from
the one configured on the machine), was working and communications (using ALTP with TLS) went up for the exchange of messages.<o:p></o:p></p>
<p class="MsoNormal">Has anyone experienced this? Does someone have a clue on how to prevent certificate reutilization on the client side?
<o:p></o:p></p>
<p class="MsoNormal">On Linux side I did not find any way of preventing the utilization of a certificate for one machine, that was issued for a different machine, having a different ip. If there is no cross checking on the server for the ip addresses on the
certificate with the ip address on the received event, I don’t have a way of non-repudiate a received event and the client can reuse the certificate for other machines, allowing the events to be received on the server.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Kind Regards<o:p></o:p></p>
<p class="MsoNormal">Alexandre Damas<o:p></o:p></p>
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