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<p class="MsoPlainText">I've done some additional testing by enabling some of the Suricata rules on a test server and I see the following. Anyone have input on what can cause them to fire ? (This is Suricata 3.2 on CentOS 7.2) . Thes are from diffrerent flows
at different times but these rules are firing frequently.<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText"><i>External source to an internal host:<o:p></o:p></i></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText">idstest suricata[9850]: [1:2220011:1] SURICATA SMTP Mime base64-decoding failed [Classification: Generic Protocol Command Decode] [Priority: 3] {TCP} xxx.xxx.xxx.xxx:2728 -> xxx.xxx.xxx.xxx:25<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText"><i>Internal to internal traffic:<o:p></o:p></i></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText">idstest suricata[7241]: [1:2220004:1] SURICATA SMTP invalid pipelined sequence [Classification: Generic Protocol Command Decode] [Priority: 3] {TCP} xxx.xxx.xxx.xxx:52298 -> xxx.xxx.xxx.xxx:25<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText"><i>Internal to internal traffic:<o:p></o:p></i></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText">idstest suricata[9850]: [1:2220019:1] SURICATA SMTP unparsable content [Classification: Generic Protocol Command Decode] [Priority: 3] {TCP} xxx.xxx.xxx.xxx:40738 -> xxx.xxx.xxx.xxx:25<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Sean Cloherty<o:p></o:p></p>
<p class="MsoNormal">InfoSec Engineer/Scientist, Lead<o:p></o:p></p>
<p class="MsoNormal"><span style="font-family:MITRE;color:#2E74B5">MITRE</span> Corporation<o:p></o:p></p>
<p class="MsoNormal">office (781) 271-3707<o:p></o:p></p>
<p class="MsoNormal">cell (781) 697-8043<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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