Snort.Conf Samples

The goal of this project is to make a set of sample snort.conf files. These will represent different size and goal installs of snort. We do not intend to provide snort.conf files that you can use without modification or understanding, but guides to help you benefit from the experience of the community as a whole.

We welcome submissions and tips to improve these files, as well as ideas for new types of configs to add.

This project is maintained by JamesMcQuaid

-- MattJonkman - 20 Mar 2007

* Diagram portraying home network defended by multiple layers of Snort Inline:

Honeywall Roo 1.4: Honeywall 1.4 has emerged from beta. 'Out of the box' it functions with a reduced Snort Inline ruleset. To use the Emerging Threats rules, you must: 1) copy the Emerging Threats rules into the Snort-inline folder, and 2) log in as root (su -) at the console, run /user/sbin/menu, and Generate IPS Rules. The strategy in this topology is to leverage Snort Inline to protect Smoothwall and the workstations. You can use Snort arrays to spread the load and eliminate a single point of failure.

Honeywall Outer Gateway: This configuration will utilize 1200 MB of 1.5 GB of RAM.

• snort_inline_Outer.conf: This Snort Inline configuration emphasizes defense against port scanning and DNS exploits. Local rules protect various Linux services and prohibit remote administration.

• blacklist.txt: The /etc/blacklist.txt file specifies incoming traffic to be blocked based upon source IP address. Based upon the Bleeding All Firewall rules.

• fencelist.txt: The /etc/fencelist.txt file specifies outgoing traffic to be blocked based upon destination IP address. Updated 4-12-2008.

• A_Novices_Guide_to_Using_Multiple_Layers_of_Snort_to_Defend_the_Home_Network.doc: Bleeding topology for the home: Honeywall Roo 1.1 and 1.2

• A_Novices_Guide_to_Using_Multiple_Layers_of_Snort_to_Defend_the_Home_Network.pdf: Bleeding topology for the home: Honeywall Roo 1.1 and 1.2

• crontab: crontab file for Honeywall which schedules reboot.pl and clean.pl

• clean.pl.txt: Clean out Honeywall's logging directories on a schedule if you have limited hard disk space.

• reboot.pl.txt: Reboot Honeywall on a schedule.

• bleeding.conf: bleeding.conf declaration for SSH ports.

Honeywall Inner Gateway: At boot, this configuration will utilize 1650 MB of 2 GB of RAM. It is suitable for home use; with a greater number of users, you will require more RAM.

• snort_inline_inner.conf: This Snort Inline configuration will use over 900 MB of RAM. All rules are set to drop. As this configuration uses the bleeding-scan.rules, you can defer the use of local rules limiting traffic on specific ports and Flow Portscan to the inner inline gateway.

• snort_inner.conf: This is the base configuration.

• UsingHoneywall.pdf: UsingHoneywall?.pdf

• InstallAndConfigureHoneywall.pdf: InstallAndConfigureHoneywall?.pdf

• Creating_A_Bootable_ISO_CD.pdf: Creating_A_Bootable_ISO_CD.pdf

Smoothwall Express 3.0: be certain to apply the two patch packages now available.

• snort_smoothwall3.conf: This configuration uses Stream5 and a large number of rules, but runs on a machine with 1 GB of RAM.

• config-ipblock_Smoothwall3: IP blocks for Smoothwall 3: includes Russian Business Network IP addresses. This file can only handle several hundred IP ranges, after which the batch file will no longer be processed. The config file in the var/ipblock folder is processed as a batch file. After the config file attains a certain size, the following error is logged in the var/log/messages file: "smoothd ipbatch buffer size exceeded". This error may also be observed in the web interface in logs.cgi under SmoothD?. If you wish to block larger numbers of malicious IP addresses, you must use another firewall. Updated 4-6-2008.

• config-hosts: 155,555 RBN affiliates, malware hosts and bad actors blacklisted for Smoothwall 3. Leave last line blank. Place in /var/smoothwall/hosts/, then rename config-hosts to config. Visit David Glosser's excellent DNS BlackHole? Project at http://malwaredomains.com/ for the latest intelligence and for information on implementing DNS Blackhole on a normal DNS server. Updated 5-12-2008.

• hosts: Protect your home from 155,555 bad domains for Smoothwall 3; placed in /var/smoothwall/hosts/. Note: with this many objects in BlackHole, you must use local loopback. Updated 5-12-2008.

• dedupe.pl.txt: Rename to dedupe.pl. Sorts and removes duplicate entries in Smoothwall's /var/smoothwall/hosts/config file; populates configNew file (which you then rename to config). With slight modification, you can also use this to dedupe IP address lists.

DNS Bind: now testing this on Free BSD.

• bindzone: Experimental. Do not use this bind zone file in a production environment unless you have tested it. A viable alternative to corporate whitelisting. Contains 155,555 domains and objects. Updated 5-12-2008.

• badblogspotsubdomains_bindformat.txt: Subdomains created by an automated process following Google's captcha application was cracked. In zone file Bind format.

Customizing your Home Firewall:

• Utilize the Emerging Threats Firewall Rules: http://www.emergingthreats.net/fwrules/ as the basis for your home firewall.

• You can learn about new, dangerous IPs by regularly reviewing your Snort logs, Symantec's Threat Explorer (http://www.symantec.com/business/security_response/threatexplorer/threats.jsp) and SRI's Multiperspective Malware Infection Analysis Page (http://www.cyber-ta.org/releases/malware-analysis/public/). If you are a Windows user, you can edit and copy the Bleeding Rules files with Notepad++ (http://sourceforge.net/projects/notepad-plus/).

• If you are using a commercial (Netgear, Linksys, etc.) router, TURN OFF Universal Plug and Play: http://isc.sans.org/diary.html?storyid=3881

• bogons: Complete list of bogons on 10-21-2007

• You can position the inline stateful packet inspection device AlphaShield? at each workstation to diminish the likelihood of the propagation of a worm in the event that an internal machine is infected. The Comodo, Kaspersky, and Sunbelt Windows firewalls also offer you configuration options to obtain this result.

• badblogspotsubdomains.txt: Plain text list of subdomains were created by an automated process following Google's captcha application was cracked. Updated 3-16-2008.

Russian Business Network:

• RussianBusinessNetworkIPs.txt (updated 5-12-2008: new IP addresses and domain listings)
• Atrivo-domains: The 26,609 domain objects in Atrivo IP space on 3-30-2008. Included in hosts and config-hosts for Smoothwall 3.0.
• Atrivo-Smoothwall-config: Smoothwall IP blocking of Atrivo-related domains. Updated 3-30-2008.
• 4000RBNDomainsAndObjects.txt
• http://www.spamhaus.org/rokso/evidence.lasso?rokso_id=ROK7740
• http://blog.washingtonpost.com/securityfix/2007/11/russian_business_network_down.html
• http://blog.washingtonpost.com/securityfix/2007/10/mapping_the_russian_business_n.html
• http://blog.washingtonpost.com/securityfix/2007/10/taking_on_the_russian_business.html
• http://www.washingtonpost.com/wp-dyn/content/story/2007/10/12/ST2007101202661.html?hpid=moreheadlines
• http://www.washingtonpost.com/wp-dyn/content/article/2007/10/12/AR2007101201700.html?sub=new
• "The Russians Go Chinese": http://www.spamhaus.org/rokso/evidence.lasso?rokso_id=ROK7829
• Bleeding RBN Signatures: http://docs.emergingthreats.net/bin/view/Main/RussianBusinessNetwork
• Jart Armin research: http://rbnexploit.blogspot.com
• Dancho Danchev research: http://ddanchev.blogspot.com/
• David Bizeul research: http://isc.sans.org/presentations/RBN_study.pdf
• Shadowserver research 'Clarifying the "guesswork" of Criminal Activity': http://www.shadowserver.org/wiki/uploads/Information/RBN-AS40989.pdf

Firekeeper for Firefox:

• BlackholeForFirekeeper.txt: Snort in the browser evil domain blocking

• BlackholeForFirekeeperInstructions.txt: Blackhole DNS in Firefox

Deprecated:

Honeywall Roo 1.1:

• snort_inline.conf: Honeywall snort-inline configuration: Bleeding Snort config for Honeywall Roo 1.1

Smoothwall Express 2.0: If you are still using Smoothwall 2.0, you will be well served to migrate to Smoothwall 3.0 as soon as possible.

• snort.in: snort.in for Smoothwall Express 2.0 Fixes 1-9

• snort.conf: snort.conf for Smoothwall Express 2.0 Fixes 1-9

• SmoothwallSnortHowTo.txt: This file explains how to set up snort on Smoothwall Express 2.0 Fixes 1-9

• blackhole.conf: 90,000 blacklisted domains for Smoothwall 2.0; leave last line blank. Want to participate in the distributed computing project? See http://doc.emergingthreats.net/bin/view/Main/SpywareListeningPost

• dnsmasq.conf: DNSMasq config for Smoothwall 2.0's blackhole

• tldblackhole.conf: Top Level Domains for Smoothwall 2.0; add to top of blackhole.conf; edit to suit your preferences

• BadMP3SitesBlackhole.txt: Evil MP3 sites targeting the kids with malware. Use in Smoothwall 2.0's blackhole.conf file.

• http://sourceforge.net/projects/smoothiemods/ Smoothwall Homebrew Mods at sourceforge

• BleedingNetworkTopologySplit?.gif: