• Great Site for Helping Write Custom Suricata Rules

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    bmeeksB
    @Snailkhan: It is not possible in pfSense to tie IDS/IPS rules or policies to the pf firewall engine. Thus it is impossible to tie IDS/IPS rules to IP source or destination pairs as evaluated by the firewall engine. That's just not how pfSense is designed. If you need this level of granularity, then pfSense is not the product for you. The best you could do is write your own custom IDS/IPS rules where you customize the Source/Destination fields of each IDS/IPS rule. I seriously doubt you want to get into that level of maintainence. Snort is an add-on volunteer-maintained package for pfSense. It is not baked into the operating system nor into the design of the firewall. Therefore its capabilities will be nowhere near as flexible as say a customized Cisco hardware/software solution might be. Later Edit: but compare the price you pay for pfSense and its Snort package to what the Cisco solution costs you . Many times compromises are necessary when taking advantage of the "free" option.
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    bmeeksB
    @gwaitsi said in Configuring pfSense/netmap for Suricata Inline IPS mode on em/igb interfaces: is it necessary to have on all interfaces, or just the ones assigned to suricata? Just the ones assigned to Suricata. But the general consensus these days with the super fast multicore CPUs most users have is that you should just disable all hardware offloading on all interfaces. It was helpful back in the days of Pentiums struggling to achieve line rate packet processing, but today's multicore CPUs generally don't break a sweat until you get to the 10 Gig area. There are several things (including some third-party packages) that can be negatively impacted by hardware offloading.
  • Quick Snort Setup Instructions for New Users

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    bmeeksB
    @qinn, it depends totally on which precise rules are enabled and what the traffic on your network actually consists of. The goal in IDS/IPS is to get no or very few alerts and blocks. That means your network is relatively secure and clients are following the rules ... . I don't mean that to say you should never get alerts, though. Just that you don't want to be receiving hundreds per hour. Once blocking is enabled that might drive you crazy as an admin. Within the IPS Polices, the Snort team has selected rules that provide security without a ton of false positive alerts.
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    bmeeksB
    @cyberzeus said in How Automatic SID Management and User Rule Overrides Work in Snort and Suricata: bmeeks - I found the following link that describes what is included in each of the 3 IPS policies.  Note there is a 4th policy - MaxDetect.  Do you know if there are any plans to implement this in the Snort package for pfSense? https://www.snort.org/documents/215 Replying to an old thread, but the answer is "yes". The new MaxDetect policy is now present and selectable in the Snort and Suricata packages. Just remember that the Snort folks recommend enabling that only for testing purposes! It is most definitely not recommended for a production network. It will generate a lot of false positives!
  • Important Info About Passlists with Suricata Inline IPS Mode

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    SteveITSS
    For those looking to create their own rules, the "sid:1000006;" part of the example is NOT a reference to an existing SID. It needs to be a unique number otherwise Suricata won't load the rule. To whitelist for a rule for an IP, search for the SID in /usr/local/etc/suricata/suricata_(interface)/rules/suricata.rules. Duplicate the conditions like "flow:from_server,established; content:"403"; http_stat_code;" into the custom rule so it matches, like pass ip 192.168.1.22/32 80 <- any any (msg: "Pass List Entry - allow all traffic to/from 192.168.1.22/32"; flow:from_server,established; content:"403"; http_stat_code;sid:1000006;) Otherwise with only the IP address, port, and unique SID it will allow all traffic for that IP. Also note the directional (<-) only allows for two directions..."both" or "left."
  • About the New Block-on-Drops Only Option in Suricata 4.0.0

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    bmeeksB
    @JasonAU: You put a lot of effort into this forum & Pfsense thank you! Seriously a lot of people would be lost without somebody doing the answering on the forum I’m having a lot of fun toying with this after work in my lab the only thing that I don’t currently understand is can I make some rules drop rather than block when I’m configured with: *Legacy mode not inline *Block on DROP only enabled *IPS Policy Security with ‘policy’ mode Snort Subscriber + ET Let’s say I like one of the rules FILE tracking GIF (1x1 pixel) from the files.rules category sounds like a good thing to help with privacy but the blocking action causes problems as often the IP that gets blocked is hosting other legitimate images in the page, Can I use SID Management to modify this rule to drop even when I have block on drop enabled? Your question leads me to believe you are misunderstanding a key piece of the puzzle.  There is no difference between DROP and BLOCK in Legacy Mode.  They are the same thing.  Both lead to the exact same result:  traffic from the offending IP address (the one that triggered the rule) is blocked by placing the SRC, DST or BOTH IP addresses from the offending packet into the snort2c pf firewall table.  After that, all further traffic from those IP addresses is blocked until the IP addresses are removed from the snort2c table.  Legacy Mode can't do what you want. The whole reason I created the new "Block-on-drops-only" option was so you can tailor rules actions to get the results you desire.  See, all rules by default from the rule set vendors come with the action set to ALERT.  With Legacy Mode Blocking, and before the new "Block-on-drops-only" option was added, any alert also generated a corresponding block.  It was an all or nothing arrangement.  When you enabled blocking, any rule that generated an alert would also cause a block.  With the new "Block-on-drops-only" option, I added some extra intelligence within the custom blocking module so that it could look at the rule action (ALERT or DROP) of the triggered rule and take the action specified.  So if the rule says ALERT, then only an alert is generated but no block is created.  If the rule says DROP, then both an alert and a block are generated. SID MGMT has options that allow you to alter rule actions from the default value of ALERT.  So now you can pick and choose which rules you want to just alert and which you want to drop (or block traffic).  This new "Block-on-drops-only" option was born out of the way the Inline IPS mode operates.  With Inline IPS Mode, you must specifically change rule actions to DROP in order to drop or block traffic.  You could also leave some rules with the default ALERT action and those rules would generate alerts but would not block or drop traffic.  That's the way most commercial proprietary Intrusion Prevention Systems operate.  So I thought it would be useful to port that same functionality (the choice of ALERT or DROP) over to Legacy Mode operation.  Hence the new "Block-on-drops-only" option. I still don't want folks to confuse Legacy Mode's use of DROP with the way IPS Mode works, though.  In Legacy Mode, even though I'm using the term "drop", the actual blocking of traffic is done the old way using libpcap to get copies of every packet traversing the interface, and when a rule fires to create a block, the IP addresses from the offending packet are copied to the snort2c table in pf to implement a firewall block.  So when I say "drop" in the context of Legacy Mode and the new "Block-on-drops-only" option, I really mean that only rules with DROP as the action will add the offender's IP address to the snort2c table.  The "drop" is really still the old fashioned block.  With Inline IPS Mode, the snort2c table is not used at all.  There is another Sticky Post here on the forum that describes the difference between Legacy Mode and Inline IPS Mode. Read both of the Sticky Posts in this forum about Passlists and Suricata.  Each of them also contains some key points about blocks, drops and Legacy vs Inline IPS modes. Bill
  • Using Snort VRT Rules With Suricata and Keeping Them Updated

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    @bmeeks said in Using Snort VRT Rules With Suricata and Keeping Them Updated: @MxcZXAKM said in Using Snort VRT Rules With Suricata and Keeping Them Updated: @bmeeks So is this the best release to reference for now? snortrules-snapshot-29160.tar.gz Yes. You want to use the most current version of the Snort 2.9.x rules with Suricata. Since Snort 2.9.16 is the current release, then the snortrules-snapshot-29160.tar.gz rules archive contains the latest ones. Very helpful, Thank you!
  • Does Snort Inline Blocking Effect All Interfaces?

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  • SNORT

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  • Suricata 7.0.8_13 Crash on 26.03

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    @SteveITS I'm not a bug hunter but I wanted to report some findings which might help with troubleshooting this issue. I have two 6100s [26.03-RELEASE] - one with a single WAN Legacy interface in Suricata, the other with two WAN Legacy interfaces in Suricata. On the assumption that perhaps it might have been a misconfiguration issue during my recent package upgrade, and not finding any direction on how to downgrade, I decided to try directly altered the two instances of "7.0.8_13" back to "7.0.8_8" in /cf/conf/config.xml file and then immediately reinstall the package under the normal package manager. This of course still results in the "7.0.8_13" version, but I thought it might find and address additional configuration issues. The result was that the configuration for the single WAN interface was completely lost and had to be rebuilt from scratch, whilst the firewall with two Suricata WAN interface configurations survived but both interfaces needed to be manually restarted (did not come back online automatically). After rebuilding the single interface and restarting the two interfaces, both had no issues with opening and displaying the BLOCKS page (without using the patch). Whilst I have no idea why it worked, i thought it might help some people out there.
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  • Suricata 7.0.8_5 on pfsense 2.8.1 hangs after enabling

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  • Snort SID Management Syntax

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    bmeeksB
    The physical files themselves (the sample SID Management Configuration files) are installed with the Snort package into /var/db/snort. Then, if it's a first-time green field installation, the contents of those sample files are migrated into the config.xml file of the firewall as Base64 encoded text by the post-installation script and stored there from then on. If they are not showing for the OP, then somehow they were accidentally deleted is my best guess. The GUI will allow them to be deleted.
  • Snort VRT Not Dowloading -Snort VRT rules md5 download failed Error

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    Sorry for zombie thread revival, but this is a top Google result and led me down the right path. For me the fix was updating the pfSense Suricata "Snort Rules Filename" from the list at https://snort.org/oinkcodes. It is required and the files available must change once in a while.
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    @bmeeks: Great advice, thanks again.
  • Suricata logs: Move to a new location

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    I really appreciate your response. Thank you.
  • Snort Alerts for a connection without FW rule

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    SteveITSS
    @elmnts shouldnt I see the initial connect in the Snort log Depends on the rule. E.g. packets from a listed IP.
  • Looks Like I Broke Snort

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    bmeeksB
    It's very simple to test the functionality of Snort. Install nmap on any laptop or PC on your network. Run a simple SYN scan against the firewall's interface IP for a network that has a Snort instance running on it with the Emerging Threats SCAN rule set enabled. nmap -sS <target_ip_address> If the above command generates connection attempt alerts, then Snort on that interface is working. If you see nothing, then Snort is either not actually running or the needed rules are not installed/enabled. Note that you won't get blocks from this test because the firewall interface IPs should all be in the automatic Pass List, but you will see ALERTS from the attempts.
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