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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Thanks Tom. I appreciate your offer, but since this is email and there is PII etc., I am not sure that is in the cards. Need another way to skin this cat.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Are there server, suricata compile errors, or suricata.yaml configuration values which I should check to eliminate the most likely causes?<o:p></o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Tom DeCanio [mailto:decanio.tom@gmail.com]
<br>
<b>Sent:</b> Thursday, January 12, 2017 20:33 PM<br>
<b>To:</b> Cloherty, Sean E <scloherty@mitre.org>; oisf-users@lists.openinfosecfoundation.org<br>
<b>Subject:</b> Re: [Oisf-users] Suricata SMTP Rules Fired - Now What...?<o:p></o:p></span></p>
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<p class="MsoNormal">Sean;<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I'm familiar with Suricata's SMTP and MIME code. If you can provide a pcap containing the offending traffic I can take a look. Send the pcap off list for the pcap if necessary.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Tom<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Thu, Jan 12, 2017 at 10:43 AM Cloherty, Sean E <<a href="mailto:scloherty@mitre.org">scloherty@mitre.org</a>> wrote:<o:p></o:p></p>
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<p class="m-2415603067348839727msoplaintext">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="m-2415603067348839727msoplaintext"> <o:p></o:p></p>
<p class="m-2415603067348839727msoplaintext"><i>External source to an internal host:</i><o:p></o:p></p>
<p class="m-2415603067348839727msoplaintext"> <o:p></o:p></p>
<p class="m-2415603067348839727msoplaintext">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="m-2415603067348839727msoplaintext"> <o:p></o:p></p>
<p class="m-2415603067348839727msoplaintext"><i>Internal to internal traffic:</i><o:p></o:p></p>
<p class="m-2415603067348839727msoplaintext"> <o:p></o:p></p>
<p class="m-2415603067348839727msoplaintext">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="m-2415603067348839727msoplaintext"> <o:p></o:p></p>
<p class="m-2415603067348839727msoplaintext"><i>Internal to internal traffic:</i><o:p></o:p></p>
<p class="m-2415603067348839727msoplaintext"> <o:p></o:p></p>
<p class="m-2415603067348839727msoplaintext">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="m-2415603067348839727msoplaintext"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Sean Cloherty<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">InfoSec Engineer/Scientist, Lead<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span class="gmailmsg"><span style="font-family:MITRE;color:#2E74B5">MITRE</span></span> Corporation<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">office
<a href="tel:(781)%20271-3707" target="_blank">(781) 271-3707</a><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">cell
<a href="tel:(781)%20697-8043" target="_blank">(781) 697-8043</a><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal">_______________________________________________<br>
Suricata IDS Users mailing list: <a href="mailto:oisf-users@openinfosecfoundation.org" target="_blank">
oisf-users@openinfosecfoundation.org</a><br>
Site: <a href="http://suricata-ids.org" target="_blank">http://suricata-ids.org</a> | Support:
<a href="http://suricata-ids.org/support/" target="_blank">http://suricata-ids.org/support/</a><br>
List: <a href="https://lists.openinfosecfoundation.org/mailman/listinfo/oisf-users" target="_blank">
https://lists.openinfosecfoundation.org/mailman/listinfo/oisf-users</a><o:p></o:p></p>
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