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    Quick Snort Setup Instructions for New Users

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    IDS/IPS
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    • BBcan177B
      BBcan177 Moderator
      last edited by

      Since this sid has been an issue for over a year, wouldn't it be appropriate to disable it from the ruleset so it doesn't come and haunt future users?

      "Experience is something you don't get until just after you need it."

      Website: http://pfBlockerNG.com
      Twitter: @BBcan177  #pfBlockerNG
      Reddit: https://www.reddit.com/r/pfBlockerNG/new/

      1 Reply Last reply Reply Quote 0
      • D
        darrenkdean
        last edited by

        Good Morning,

        Has anyone had success in configuring Snort to allow apple devices to communicate with the Apple Store & iCloud?  I have followed the quick setup guide, rule configuration, & everything appears to be working great, with the exception of iPad's & iPhone's not being able to communicate with the Apple Store & not able to restore from iCloud Backup.  Any direction on how best to allow this connectivity would be greatly appreciated.

        Best-

        Darren

        1 Reply Last reply Reply Quote 0
        • bmeeksB
          bmeeks
          last edited by

          @BBcan177:

          Since this sid has been an issue for over a year, wouldn't it be appropriate to disable it from the ruleset so it doesn't come and haunt future users?

          I am leery of permanently disabling a rule within the GUI code.

          Bill

          1 Reply Last reply Reply Quote 0
          • bmeeksB
            bmeeks
            last edited by

            @darrenkdean:

            Good Morning,

            Has anyone had success in configuring Snort to allow apple devices to communicate with the Apple Store & iCloud?  I have followed the quick setup guide, rule configuration, & everything appears to be working great, with the exception of iPad's & iPhone's not being able to communicate with the Apple Store & not able to restore from iCloud Backup.  Any direction on how best to allow this connectivity would be greatly appreciated.

            Best-

            Darren

            I have no problem with this working in my home network using Snort and pfSense 2.2.  Have you checked to see if some particular alert is firing and generating a block?  You can check the ALERTS or BLOCKED tabs to see what Snort is doing.

            Bill

            1 Reply Last reply Reply Quote 0
            • ?
              A Former User
              last edited by

              @BBcan177:

              Since this sid has been an issue for over a year, wouldn't it be appropriate to disable it from the ruleset so it doesn't come and haunt future users?

              What, you mean ET actually disabling a non functioning rule? Come on it's ET we are talking about here.  ;)

              I'm on bmeek's side here. Permanently disabling a rule shouldn't be the solution. Not unless we can get a premade list out anyway (hint:new guide).

              1 Reply Last reply Reply Quote 0
              • D
                darrenkdean
                last edited by

                Good Day,

                I'm running into an issue with the Ooma IP Telephone Service whereby anytime a telephone call is made or received, it trips the following rule in Snort:

                ET TROJAN Possible Downadup/Conficker-C P2P encrypted traffic UDP Ping Packet (bit value 5)

                I created a Firewall Alias called Ooma with the following data for the Ooma Servers:
                70.42.139.0/24         Ooma
                208.83.244.0/22 Ooma, Inc.

                I then added the Alias to the Snort Pass List, checking the Ooma Alias, & leaving all other boxes unchecked.  I've clearly missed something, as the alerts are still being triggered & blocked, inspite of having added the correct Ooma Servers.  Any thoughts?

                Best-

                Darren

                1 Reply Last reply Reply Quote 0
                • ?
                  A Former User
                  last edited by

                  Did you stop/start the snort interface after adding that to the passlist?

                  1 Reply Last reply Reply Quote 0
                  • bmeeksB
                    bmeeks
                    last edited by

                    @darrenkdean:

                    Good Day,

                    I'm running into an issue with the Ooma IP Telephone Service whereby anytime a telephone call is made or received, it trips the following rule in Snort:

                    ET TROJAN Possible Downadup/Conficker-C P2P encrypted traffic UDP Ping Packet (bit value 5)

                    I created a Firewall Alias called Ooma with the following data for the Ooma Servers:
                    70.42.139.0/24         Ooma
                    208.83.244.0/22 Ooma, Inc.

                    I then added the Alias to the Snort Pass List, checking the Ooma Alias, & leaving all other boxes unchecked.  I've clearly missed something, as the alerts are still being triggered & blocked, inspite of having added the correct Ooma Servers.  Any thoughts?

                    Best-

                    Darren

                    Also make sure the new Pass List is actually assigned to your Snort interface by choosing it in the PASS LIST drop-down box on the INTERFACE SETTINGS tab.  Save the change and then restart Snort on the interface as @jflsakfja suggested.

                    Additionally, I don't recommend unchecking the other Pass List checkboxes.  You generally don't ever want to do that except in very unusual situations.  Yours does not sound like one where I would uncheck those default-checked boxes.

                    Bill

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                    • D
                      darrenkdean
                      last edited by

                      Excellent, thank you both!  I went back & changed the settings per your guidance & the telephone service is now working.  Can't thank you enough for your help!  Alerts are still being generated, but no longer blocked.  Is there any reason why I would not want to suppress these alerts?

                      Best-

                      Darren

                      1 Reply Last reply Reply Quote 0
                      • bmeeksB
                        bmeeks
                        last edited by

                        @darrenkdean:

                        Excellent, thank you both!  I went back & changed the settings per your guidance & the telephone service is now working.  Can't thank you enough for your help!  Alerts are still being generated, but no longer blocked.  Is there any reason why I would not want to suppress these alerts?

                        Best-

                        Darren

                        You can suppress them if you wish, but depending on how you do it you may expose yourself to a real attack (as opposed to the false positive you are likely seeing now).  Here is what I would do:

                        You know the IP address in question (your phone system), so create a suppress list rule by IP address.  The easiest way to accomplish this is on the ALERTS tab.  Click the plus (+) icon beside the IP address you don't want to block on one of the alert rows.  This will create a suppress list entry of type "track by IP".  It will be either source (SRC) or destination (DST) depending on which address column you clicked.  The entry will be for that specific IP.  If you want to suppress by an IP block instead, then after creating the entry as described previously, go to the SUPPRESS LIST tab, find the newly created list and edit it.  Change the IP address to a CIDR block.

                        Bill

                        1 Reply Last reply Reply Quote 0
                        • D
                          darrenkdean
                          last edited by

                          Good Afternoon,

                          I have configured Snort according to the guide & everything works great on the WAN.  I have created a LAN Interface & mirrored the rules for both.  When I go to start Snort on the LAN, I am getting the following error:

                          snort[93176]: server /usr/pbi/snort-amd64/etc/snort/appid//odp/lua/service_EIP.lua: error validating …snort-amd64/etc/snort/appid//odp/libs/DetectorCommon.lua:318: table index is nil

                          I have searched for documentation on this, but have been unable to find out what it is &/or why Snort will not start on the LAN interface.  Any guidance or suggestions would be greatly appreciated.

                          Best-

                          Darren

                          1 Reply Last reply Reply Quote 0
                          • M
                            Mr. Jingles
                            last edited by

                            @darrenkdean:

                            Good Afternoon,

                            I have configured Snort according to the guide & everything works great on the WAN.  I have created a LAN Interface & mirrored the rules for both.  When I go to start Snort on the LAN, I am getting the following error:

                            snort[93176]: server /usr/pbi/snort-amd64/etc/snort/appid//odp/lua/service_EIP.lua: error validating …snort-amd64/etc/snort/appid//odp/libs/DetectorCommon.lua:318: table index is nil

                            I have searched for documentation on this, but have been unable to find out what it is &/or why Snort will not start on the LAN interface.  Any guidance or suggestions would be greatly appreciated.

                            Best-

                            Darren

                            Confirmed. My system log is filled with this too:

                            snort[4022]: server /usr/pbi/snort-amd64/etc/snort/appid//odp/lua/service_EIP.lua: error validating ...snort-amd64/etc/snort/appid//odp/libs/DetectorCommon.lua:318: table index is nil

                            Snort starts on all interfaces 'though, yet it is cluttering up the logs with this constantly repeating message.

                            pfSense 2.1.5 X64, Snort 2.9.7.0 pkg 3.2.3

                            6 and a half billion people know that they are stupid, agressive, lower life forms.

                            1 Reply Last reply Reply Quote 0
                            • bmeeksB
                              bmeeks
                              last edited by

                              @darrenkdean:

                              Good Afternoon,

                              I have configured Snort according to the guide & everything works great on the WAN.  I have created a LAN Interface & mirrored the rules for both.  When I go to start Snort on the LAN, I am getting the following error:

                              snort[93176]: server /usr/pbi/snort-amd64/etc/snort/appid//odp/lua/service_EIP.lua: error validating …snort-amd64/etc/snort/appid//odp/libs/DetectorCommon.lua:318: table index is nil

                              I have searched for documentation on this, but have been unable to find out what it is &/or why Snort will not start on the LAN interface.  Any guidance or suggestions would be greatly appreciated.

                              Best-

                              Darren

                              It would be better if you start a new thread in the IDS/IPS sub-forum.  This thread was designed to contain just the how-to instructions.

                              The answer to your problem is also posted in a previous thread here: https://forum.pfsense.org/index.php?topic=89393.msg495651#msg495651, but I will repeat it here.  This is a known syntax error in the OpenAppID rules package from the Snort VRT.  They committed to fix it in a mailing list post about two weeks ago.  It appears they have not yet.  You can disable the OpenAppID preprocessor to make the error go away.  Unless you have also written your own custom rules to use the OpenAppID signatures, they aren't working anyway.

                              Bill

                              1 Reply Last reply Reply Quote 0
                              • T
                                tty0
                                last edited by

                                Very simple guide bmeeks, thank you for taking the time to explain this to us new users. Followed another guide and I kept having snort ban websites I was visiting.

                                1 Reply Last reply Reply Quote 0
                                • 2
                                  2chemlud Banned
                                  last edited by

                                  Hi!

                                  How about adding a little bit of info specific to nano users running snort? ;-)

                                  Maybe somethink like this:

                                  https://forum.pfsense.org/index.php?topic=106725.msg594731#msg594731

                                  Regards

                                  chemlud

                                  1 Reply Last reply Reply Quote 0
                                  • A
                                    AR15USR
                                    last edited by

                                    Hi bmeeks/jflsakfja,

                                    This post was originally done a few years ago, how valid is the setup in post 1 and the rule configuration in post 3 these days?

                                    2.6.0-RELEASE

                                    1 Reply Last reply Reply Quote 0
                                    • T
                                      THS
                                      last edited by

                                      Hey. Thanks for this useful post.
                                      Btw this list is 3 years old. Is it still (mostly) up to date ?

                                      Also I have a few repeating alerts I can't figure out. Can you help ?

                                      1:2018959.  ET POLICY PE EXE or DLL Windows file download HTTP
                                      1:28039.    INDICATOR-COMPROMISE Suspicious .pw dns query
                                      119:33.  (http_inspect) UNESCAPED SPACE IN HTTP URI

                                      Thanks !

                                      @jflsakfja:

                                      The Missing Part to Quick Snort Setup Instructions for New Users

                                      In tab "Rules", under "Category" select:
                                      (–- means blank table at time of writing)

                                      DONE > emerging-activex > all

                                      DONE > emerging-attack_responses > all

                                      DONE > emerging-botcc > all

                                      DONE > emerging-chat > all except:
                                      2010784 ET CHAT Facebook Chat (send message)
                                      2010785 ET CHAT Facebook Chat (buddy list)
                                      2010786 ET CHAT Facebook Chat (settings)
                                      2010819 ET CHAT Facebook Chat using XMPP
                                      2002327 ET CHAT Google Talk (Jabber) Client Login
                                      2002334 ET CHAT Google IM traffic Jabber client sign-on
                                      2001241 ET CHAT MSN file transfer request
                                      2001242 ET CHAT MSN file transfer accept
                                      2001243 ET CHAT MSN file transfer reject
                                      2001682 ET CHAT MSN IM Poll via HTTP
                                      2002192 ET CHAT MSN status change
                                      2008289 ET CHAT Possible MSN Messenger File Transfer
                                      2009375 ET CHAT General MSN Chat Activity
                                      2009376 ET CHAT MSN User-Agent Activity

                                      DONE > emerging-ciarmy > all

                                      DONE > emerging-compromised > all

                                      DONE > emerging-current_events > all

                                      DONE > emerging-deleted > ---

                                      DONE > emerging-dns > all except:
                                      2008446 ET DNS Excessive DNS Responses with 1 or more RR's (100+ in 10
                                      seconds) - possible Cache Poisoning Attempt
                                      2008470 ET DNS Excessive NXDOMAIN responses - Possible DNS Backscatter or Domain Generation Algorithm Lookups
                                      2001117 ET DNS Standard query response, Name Error

                                      DONE > emerging-dos > all

                                      DONE > emerging-drop > all

                                      DONE > emerging-dshield > all

                                      DONE > emerging-exploit > all except:
                                      2001058 ET EXPLOIT libpng tRNS overflow attempt
                                      2002913 ET EXPLOIT VNC Client response
                                      2002914 ET EXPLOIT VNC Server VNC Auth Offer
                                      2002919 ET EXPLOIT VNC Good Authentication Reply
                                      2002915 ET EXPLOIT VNC Authentication Reply
                                      2002758 ET EXPLOIT WMF Escape Record Exploit - Version 1
                                      2002742 ET EXPLOIT WMF Escape Record Exploit - Version 3

                                      DONE > emerging-ftp > all

                                      DONE > emerging-games > all

                                      DONE > emerging-icmp > ---

                                      DONE > emerging-icmp_info > ---

                                      DONE > emerging-imap > ---

                                      DONE > emerging-inappropriate > all except:
                                      2002925 ET INAPPROPRIATE Google Image Search, Safe Mode Off
                                      2001608 ET INAPPROPRIATE Likely Porn

                                      DONE > emerging-info > all except:
                                      2014472 ET INFO JAVA - Java Archive Download
                                      2014473 ET INFO JAVA - Java Archive Download By Vulnerable Client
                                      2014819 ET INFO Packed Executable Download
                                      2015016 ET INFO FTP STOR to External Network
                                      2015561 ET INFO PDF Using CCITTFax Filter
                                      2015744 ET INFO EXE IsDebuggerPresent (Used in Malware Anti-Debugging)
                                      2016360 ET INFO JAVA - ClassID
                                      2016361 ET INFO JAVA - ClassID
                                      2016404 ET INFO MPEG Download Over HTTP (1)

                                      DONE > emerging-malware > all except:
                                      2008438 ET MALWARE Possible Windows executable sent when remote host claims to send a Text File

                                      DONE > emerging-misc > all

                                      DONE > emerging-mobile_malware > all except:
                                      2012251 ET MOBILE_MALWARE Google Android Device HTTP Request
                                      2012848 ET MOBILE_MALWARE Possible Mobile Malware POST of IMEI International Mobile Equipment Identity in URI

                                      DONE > emerging-netbios > all

                                      DONE > emerging-p2p > all except:
                                      2000369 ET P2P BitTorrent Announce
                                      2007727 ET P2P possible torrent download
                                      2008581 ET P2P BitTorrent DHT ping request
                                      2008583 ET P2P BitTorrent DHT nodes reply
                                      2008585 ET P2P BitTorrent DHT announce_peers request
                                      2010144 ET P2P Vuze BT UDP Connection (5)
                                      2011699 ET P2P Bittorrent P2P Client User-Agent (Transmission/1.x)

                                      *emerging-policy > all except:
                                      2000419 ET POLICY PE EXE or DLL Windows file download
                                      2000428 ET POLICY ZIP file download
                                      2001115 ET POLICY MSI (microsoft installer file) download
                                      2003595 ET POLICY exe download via HTTP - Informational
                                      2001898 ET POLICY eBay Bid Placed
                                      2001907 ET POLICY eBay Placing Item for sale
                                      2001908 ET POLICY eBay View Item
                                      2001909 ET POLICY eBay Watch This Item
                                      2003303 ET POLICY FTP Login Attempt (non-anonymous)
                                      2003410 ET POLICY FTP Login Successful
                                      2003121 ET POLICY docs.google.com Activity
                                      2003597 ET POLICY Google Calendar in Use
                                      2002801 ET POLICY Google Desktop User-Agent Detected
                                      2002838 ET POLICY Google Search Appliance browsing the Internet
                                      2000035 ET POLICY Hotmail Inbox Access
                                      2000036 ET POLICY Hotmail Message Access
                                      2000037 ET POLICY Hotmail Compose Message Access
                                      2000038 ET POLICY Hotmail Compose Message Submit
                                      2000039 ET POLICY Hotmail Compose Message Submit Data
                                      2008238 ET POLICY Hotmail Inbox Access
                                      2008239 ET POLICY Hotmail Message Access
                                      2008240 ET POLICY Hotmail Compose Message Access
                                      2008242 ET POLICY Hotmail Access Full Mode
                                      2006408 ET POLICY HTTP Request on Unusual Port Possibly Hostile
                                      2006409 ET POLICY HTTP POST on unusual Port Possibly Hostile
                                      2002330 ET POLICY Google Talk TLS Client Traffic
                                      2002332 ET POLICY Google IM traffic Windows client user sign-on
                                      2002333 ET POLICY Google IM traffic friend invited
                                      2002878 ET POLICY iTunes User Agent
                                      2002722 ET POLICY MP3 File Transfer Outbound
                                      2002723 ET POLICY MP3 File Transfer Inbound
                                      2001114 ET POLICY Mozilla XPI install files download
                                      2001973 ET POLICY SSH Server Banner Detected on Expected Port
                                      2001974 ET POLICY SSH Client Banner Detected on Expected Port
                                      2001975 ET POLICY SSHv2 Server KEX Detected on Expected Port
                                      2001976 ET POLICY SSHv2 Client KEX Detected on Expected Port
                                      2001977 ET POLICY SSHv2 Client New Keys detected on Expected Port
                                      2001978 ET POLICY SSH session in progress on Expected Port
                                      2001979 ET POLICY SSH Server Banner Detected on Unusual Port
                                      2001980 ET POLICY SSH Client Banner Detected on Unusual Port
                                      2001981 ET POLICY SSHv2 Server KEX Detected on Unusual Port
                                      2001982 ET POLICY SSHv2 Client KEX Detected on Unusual Port
                                      2001983 ET POLICY SSHv2 Client New Keys Detected on Unusual Port
                                      2001984 ET POLICY SSH session in progress on Unusual Port
                                      2013031 ET POLICY Python-urllib/ Suspicious User Agent
                                      2013414 ET POLICY Executable served from Amazon S3
                                      2014297 ET POLICY Vulnerable Java Version 1.7.x Detected
                                      2012647 ET POLICY Dropbox.com Offsite File Backup in Use
                                      2012648 ET POLICY Dropbox Client Broadcasting
                                      2014313 ET POLICY Executable Download From DropBox

                                      DONE > emerging-pop3 > ---

                                      DONE > emerging-rbn-malvertisers > all

                                      DONE > emerging-rbn > all

                                      DONE > emerging-rpc > ---

                                      DONE > emerging-scada > all

                                      DONE > emerging-scan > all except
                                      2002992 ET SCAN Rapid POP3 Connections - Possible Brute Force Attack
                                      2002993 ET SCAN Rapid POP3S Connections - Possible Brute Force Attack
                                      2002994 ET SCAN Rapid IMAP Connections - Possible Brute Force Attack
                                      2002995 ET SCAN Rapid IMAPS Connections - Possible Brute Force Attack

                                      DONE > emerging-shellcode > all except
                                      2011803 ET SHELLCODE Possible TCP x86 JMP to CALL Shellcode Detected
                                      2012252 ET SHELLCODE Common 0a0a0a0a Heap Spray String
                                      2012257 ET SHELLCODE Common %0c%0c%0c%0c Heap Spray String
                                      2012510 ET SHELLCODE UTF-8/16 Encoded Shellcode
                                      2013222 ET SHELLCODE Excessive Use of HeapLib Objects Likely Malicious Heap Spray Attempt
                                      2013267 ET SHELLCODE Hex Obfuscated JavaScript Heap Spray 0a0a0a0a

                                      DONE > emerging-smtp > all

                                      DONE > emerging-snmp > all

                                      DONE > emerging-sql > all

                                      DONE > emerging-telnet > all

                                      DONE > emerging-tftp > all

                                      DONE > emerging-tor > all

                                      emerging-trojan > all except

                                      DONE > emerging-user_agents > all except:
                                      2010697 ET USER_AGENTS Suspicious User-Agent Beginning with digits - Likely spyware/trojan

                                      DONE > emerging-voip > all

                                      DONE > emerging-web_client > all except
                                      2011347 ET WEB_CLIENT Possible String.FromCharCode Javascript Obfuscation Attempt
                                      2011507 ET WEB_CLIENT PDF With Embedded File
                                      2010518 ET WEB_CLIENT Possible HTTP 404 XSS Attempt (External Source)
                                      2012119 ET WEB_CLIENT Possible Hex Obfuscation Usage On Webpage
                                      2012205 ET WEB_CLIENT Possible Malicious String.fromCharCode with charCodeAt String
                                      2012266 ET WEB_CLIENT Hex Obfuscation of unescape % Encoding
                                      2012272 ET WEB_CLIENT Hex Obfuscation of eval % Encoding
                                      2012398 ET WEB_CLIENT Hex Obfuscation of replace Javascript Function % Encoding

                                      DONE > emerging-web_server > all except
                                      2003099 ET WEB_SERVER Poison Null Byte

                                      emerging-web_specific_apps > all except:
                                      2010890 ET WEB_SPECIFIC_APPS phpBB3 registration (Step1 GET)
                                      2010891 ET WEB_SPECIFIC_APPS phpBB3 registration (Step2 POST)
                                      2010892 ET WEB_SPECIFIC_APPS phpBB3 registration (Step3 GET)
                                      2010893 ET WEB_SPECIFIC_APPS phpBB3 registration (Step4 POST)

                                      DONE > emerging-worm > all

                                      DONE > GPLv2 community rules > all except
                                      254 DNS SPOOF query response with TTL of 1 min. and no authority
                                      384 PROTOCOL-ICMP PING
                                      385 PROTOCOL-ICMP traceroute
                                      399 PROTOCOL-ICMP Destination Unreachable Host Unreachable
                                      402 PROTOCOL-ICMP Destination Unreachable Port Unreachable
                                      408 PROTOCOL-ICMP Echo Reply
                                      540 POLICY-SOCIAL Microsoft MSN message
                                      648 INDICATOR-SHELLCODE x86 NOOP
                                      649 INDICATOR-SHELLCODE x86 setgid 0
                                      1200 INDICATOR-COMPROMISE Invalid URL
                                      1201 INDICATOR-COMPROMISE 403 Forbidden
                                      1292 INDICATOR-COMPROMISE directory listing
                                      1390 INDICATOR-SHELLCODE x86 inc ebx NOOP
                                      1394 INDICATOR-SHELLCODE x86 inc ecx NOOP
                                      1437 FILE-IDENTIFY Microsoft Windows Media download detected
                                      1841 FILE-OTHER Oracle Javascript URL host spoofing attempt
                                      1846 POLICY-MULTIMEDIA vncviewer Java applet download attempt
                                      1852 SERVER-WEBAPP robots.txt access
                                      1986 POLICY-SOCIAL Microsoft MSN outbound file transfer request
                                      1988 POLICY-SOCIAL Microsoft MSN outbound file transfer accept
                                      1989 POLICY-SOCIAL Microsoft MSN outbound file transfer rejected
                                      1990 POLICY-SOCIAL Microsoft MSN user search
                                      1991 POLICY-SOCIAL Microsoft MSN login attempt
                                      2180 PUA-P2P BitTorrent announce request
                                      2181 PUA-P2P BitTorrent transfer
                                      2707 FILE-IMAGE JPEG parser multipacket heap overflow
                                      3463 SERVER-WEBAPP awstats access
                                      25518 OS-OTHER Apple iPod User-Agent detected
                                      25519 OS-OTHER Apple iPad User-Agent detected
                                      25520 OS-OTHER Apple iPhone User-Agent detected
                                      25521 OS-OTHER Android User-Agent detected
                                      25522 OS-OTHER Nokia User-Agent detected
                                      25523 OS-OTHER Samsung User-Agent detected
                                      25524 OS-OTHER Kindle User-Agent detected
                                      25525 OS-OTHER Nintendo User-Agent detected

                                      *IPS Policy - Security > all except
                                      4152 BROWSER-PLUGINS Microsoft Windows Media Player 6.4 ActiveX object access
                                      19436 BROWSER-IE Microsoft Internet Explorer CStyleSheetRule array memory corruption attempt

                                      Suppression List:
                                      #GLOBAL

                                      gen_id 1

                                      suppress gen_id 1, sig_id 536
                                      suppress gen_id 1, sig_id 648
                                      suppress gen_id 1, sig_id 653
                                      suppress gen_id 1, sig_id 1390
                                      suppress gen_id 1, sig_id 2452
                                      suppress gen_id 1, sig_id 11192
                                      suppress gen_id 1, sig_id 15306
                                      suppress gen_id 1, sig_id 16313
                                      suppress gen_id 1, sig_id 17458
                                      suppress gen_id 1, sig_id 20583
                                      suppress gen_id 1, sig_id 23098
                                      suppress gen_id 1, sig_id 2000334
                                      suppress gen_id 1, sig_id 2008120
                                      suppress gen_id 1, sig_id 2010516
                                      suppress gen_id 1, sig_id 20122758
                                      suppress gen_id 1, sig_id 2014518
                                      suppress gen_id 1, sig_id 2014520
                                      suppress gen_id 1, sig_id 2100366
                                      suppress gen_id 1, sig_id 2100368
                                      suppress gen_id 1, sig_id 2100651
                                      suppress gen_id 1, sig_id 2101390
                                      suppress gen_id 1, sig_id 2101424
                                      suppress gen_id 1, sig_id 2102314
                                      suppress gen_id 1, sig_id 2103134
                                      suppress gen_id 1, sig_id 2500056
                                      suppress gen_id 1, sig_id 100000230
                                      suppress gen_id 3, sig_id 14772
                                      #(http_inspect) DOUBLE DECODING ATTACK
                                      suppress gen_id 119, sig_id 2
                                      #(http_inspect) BARE BYTE UNICODE ENCODING
                                      suppress gen_id 119, sig_id 4
                                      #(http_inspect) IIS UNICODE CODEPOINT ENCODING
                                      suppress gen_id 119, sig_id 7
                                      #(http_inspect) NON-RFC DEFINED CHAR [**]
                                      suppress gen_id 119, sig_id 14
                                      #(http_inspect) UNKNOWN METHOD
                                      suppress gen_id 119, sig_id 31
                                      #(http_inspect) SIMPLE REQUEST
                                      suppress gen_id 119, sig_id 32
                                      #(http_inspect) NO CONTENT-LENGTH OR TRANSFER-ENCODING IN HTTP RESPONSE
                                      suppress gen_id 120, sig_id 2
                                      #(http_inspect) NO CONTENT-LENGTH OR TRANSFER-ENCODING IN HTTP RESPONSE
                                      suppress gen_id 120, sig_id 3
                                      #(http_inspect) HTTP RESPONSE HAS UTF CHARSET WHICH FAILED TO NORMALIZE
                                      suppress gen_id 120, sig_id 4
                                      #(http_inspect) HTTP RESPONSE GZIP DECOMPRESSION FAILED
                                      suppress gen_id 120, sig_id 6
                                      #(http_inspect) INVALID CONTENT-LENGTH OR CHUNK SIZE
                                      suppress gen_id 120, sig_id 8
                                      #(http_inspect) JAVASCRIPT OBFUSCATION LEVELS EXCEEDS 1
                                      suppress gen_id 120, sig_id 9

                                      Unknown

                                      suppress gen_id 120, sig_id 10
                                      #(smtp) Attempted response buffer overflow: 1448 chars
                                      suppress gen_id 124, sig_id 3
                                      #(ftp_telnet) Invalid FTP Command
                                      suppress gen_id 125, sig_id 2
                                      #(ssp_ssl) Invalid Client HELLO after Server HELLO Detected
                                      suppress gen_id 137, sig_id 1
                                      #(IMAP) Unknown IMAP4 command
                                      suppress gen_id 141, sig_id 1

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                                      • MikeV7896M
                                        MikeV7896
                                        last edited by

                                        @THS:

                                        Hey. Thanks for this useful post.
                                        Btw this list is 3 years old. Is it still (mostly) up to date ?

                                        Also I have a few repeating alerts I can't figure out. Can you help ?

                                        1:2018959.  ET POLICY PE EXE or DLL Windows file download HTTP
                                        1:28039.    INDICATOR-COMPROMISE Suspicious .pw dns query
                                        119:33.  (http_inspect) UNESCAPED SPACE IN HTTP URI

                                        Thanks !

                                        A few options may have had slight name changes, and I think one has been removed since it was written, but for the most part it's still good.

                                        On your repeating alerts…

                                        The first one looks like an alert that a .exe or .dll file is being downloaded from the internet. I can see why that would be a common one. Probably safe to suppress or disable this rule, depending on your preference, unless your users shouldn't be downloading executable binary files to their computers.

                                        The second one looks like an alert that a potentially suspicious .pw domain is being looked up using DNS. You might want to check the host(s) that the alert is showing up for to make sure there isn't any malicious software on it/them. Of course, if your hosts regularly access systems that are legitimate in the .pw TLD, then you might want to suppress or disable this one.

                                        The third is a rather common one regarding a space character in an HTTP URL that isn't being formatted with an escape sequence (i.e. %20), which should be done to adhere to proper specs, but sometimes isn't. This one should be safe to suppress or disable.

                                        Edit to add: Your second alert could also be caused by a torrent client, connecting to a user in the country that uses the .pw TLD for data.

                                        The S in IOT stands for Security

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                                        • T
                                          THS
                                          last edited by

                                          Hey you were right. It was because of bittorrent. It was blocking all traffic to .PW

                                          I turned that rule off.

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                                          • H
                                            hamed_forum
                                            last edited by

                                            the google block in snort beacuse (portscan) TCP Portscan
                                            i must whats do?
                                            Portscan Detection
                                            protocol tcp
                                            scan type all
                                            Sensitivity low

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