OSSEC Tips & Tricks

OSSEC Tips & Tricks

OSSEC is an Open Source Host-based Intrusion Detection System that performs log analysis, file integrity checking, policy monitoring, rootkit detection, real-time alerting and active response.

Installation

Database support

Enable database support:

cd src
make setdb
Error: PostgreSQL client libraries not installed.

Info: Compiled with MySQL support.

then ran ./install.sh

GNU/Debian (Ubuntu)

See: OSSEC Download

    # wget -O - http://ossec.alienvault.com/repos/apt/conf/ossec-key.gpg.key | apt-key add -
    # echo "deb http://ossec.alienvault.com/repos/apt/debian wheezy main" >> /etc/apt/sources.list  
      (change wheezy for your Debian distribution)
    # apt-get update
    # apt-get install ossec-hids  (or ossec-hids-agent)

change “wheezy” to “jessie” to use with Ubuntu LTS 12.04 (14.04)

Ansible deploy

Windows (Agent)

Configuration

Add new agent

Server side

Make sure you have port 1514/udp (default) open for agents

 # ./manage_agents

'(A)dd new Agent' and copy agent key from '(E)xtract key for an agent'

****************************************
* OSSEC HIDS v2.7.1 Agent manager.     *
* The following options are available: *
****************************************
   (A)dd an agent (A).
   (E)xtract key for an agent (E).
   (L)ist already added agents (L).
   (R)emove an agent (R).
   (Q)uit.
Choose your action: A,E,L,R or Q:

Agent side

 ./manage_agents

paste agent key into '(I)mport key from the server'

****************************************
* OSSEC HIDS v2.8 Agent manager.     *
* The following options are available: *
****************************************
   (I)mport key from the server (I).
   (Q)uit.
Choose your action: I or Q:

Local/master configuration (Debian)

/var/ossec/etc/ossec.conf

<ossec_config>
  <global>
    <email_notification>yes</email_notification>
    <email_to>root@xxxx</email_to>
    <smtp_server>YOUR-SMTP-SERVER</smtp_server>
    <email_from>MAILFROM-EMAIL</email_from>

    # List of IP addresses that should never be blocked by the 
    # active response (one per element). This option is only valid in server and local installs.
    <white_list>127.0.0.1</white_list>
    
    # If set, “X-IDS-OSSEC: ” will be added to the email headers with the specified value.
    <email_idsname>OSSEC</email_idsname>
  </global>

  <rules>
    <include>rules_config.xml</include>
    <include>pam_rules.xml</include>
    <include>sshd_rules.xml</include>
    <include>telnetd_rules.xml</include>
    <include>syslog_rules.xml</include>
    <include>arpwatch_rules.xml</include>
    <include>symantec-av_rules.xml</include>
    <include>symantec-ws_rules.xml</include>
    <include>pix_rules.xml</include>
    <include>named_rules.xml</include>
    <include>smbd_rules.xml</include>
    <include>vsftpd_rules.xml</include>
    <include>pure-ftpd_rules.xml</include>
    <include>proftpd_rules.xml</include>
    <include>ms_ftpd_rules.xml</include>
    <include>ftpd_rules.xml</include>
    <include>hordeimp_rules.xml</include>
    <include>roundcube_rules.xml</include>
    <include>wordpress_rules.xml</include>
    <include>cimserver_rules.xml</include>
    <include>vpopmail_rules.xml</include>
    <include>vmpop3d_rules.xml</include>
    <include>courier_rules.xml</include>
    <include>web_rules.xml</include>
    <include>web_appsec_rules.xml</include>
    <include>apache_rules.xml</include>
    <include>nginx_rules.xml</include>
    <include>php_rules.xml</include>
    <include>mysql_rules.xml</include>
    <include>postgresql_rules.xml</include>
    <include>ids_rules.xml</include>
    <include>squid_rules.xml</include>
    <include>firewall_rules.xml</include>
    <include>cisco-ios_rules.xml</include>
    <include>netscreenfw_rules.xml</include>
    <include>sonicwall_rules.xml</include>
    <include>postfix_rules.xml</include>
    <include>sendmail_rules.xml</include>
    <include>imapd_rules.xml</include>
    <include>mailscanner_rules.xml</include>
    <include>dovecot_rules.xml</include>
    <include>ms-exchange_rules.xml</include>
    <include>racoon_rules.xml</include>
    <include>vpn_concentrator_rules.xml</include>
    <include>spamd_rules.xml</include>
    <include>msauth_rules.xml</include>
    <include>mcafee_av_rules.xml</include>
    <include>trend-osce_rules.xml</include>
    <include>ms-se_rules.xml</include>
    <!-- <include>policy_rules.xml</include> -->
    <include>zeus_rules.xml</include>
    <include>solaris_bsm_rules.xml</include>
    <include>vmware_rules.xml</include>
    <include>ms_dhcp_rules.xml</include>
    <include>asterisk_rules.xml</include>
    <include>ossec_rules.xml</include>
    <include>attack_rules.xml</include>
    <include>openbsd_rules.xml</include>
    <include>clam_av_rules.xml</include>
    <include>bro-ids_rules.xml</include>
    <include>dropbear_rules.xml</include>
    <include>local_rules.xml</include>
  </rules>  

  <syscheck>
    <!-- Frequency that syscheck is executed - default to every 22 hours -->
    <frequency>79200</frequency>
    
    <!-- Directories to check  (perform all possible verifications) -->
    <directories check_all="yes">/etc,/usr/bin,/usr/sbin</directories>
    <directories check_all="yes">/bin,/sbin</directories>

    <!-- Files/directories to ignore -->
    <ignore>/etc/mtab</ignore>
    <ignore>/etc/mnttab</ignore>
    <ignore>/etc/hosts.deny</ignore>
    <ignore>/etc/mail/statistics</ignore>
    <ignore>/etc/random-seed</ignore>
    <ignore>/etc/adjtime</ignore>
    <ignore>/etc/httpd/logs</ignore>
    <ignore>/etc/utmpx</ignore>
    <ignore>/etc/wtmpx</ignore>
    <ignore>/etc/cups/certs</ignore>
    <ignore>/etc/dumpdates</ignore>
    <ignore>/etc/svc/volatile</ignore>

    <!-- Windows files to ignore -->
    <ignore>C:\WINDOWS/System32/LogFiles</ignore>
    <ignore>C:\WINDOWS/Debug</ignore>
    <ignore>C:\WINDOWS/WindowsUpdate.log</ignore>
    <ignore>C:\WINDOWS/iis6.log</ignore>
    <ignore>C:\WINDOWS/system32/wbem/Logs</ignore>
    <ignore>C:\WINDOWS/system32/wbem/Repository</ignore>
    <ignore>C:\WINDOWS/Prefetch</ignore>
    <ignore>C:\WINDOWS/PCHEALTH/HELPCTR/DataColl</ignore>
    <ignore>C:\WINDOWS/SoftwareDistribution</ignore>
    <ignore>C:\WINDOWS/Temp</ignore>
    <ignore>C:\WINDOWS/system32/config</ignore>
    <ignore>C:\WINDOWS/system32/spool</ignore>
    <ignore>C:\WINDOWS/system32/CatRoot</ignore>
  </syscheck>

  <rootcheck>
    <rootkit_files>/var/ossec/etc/shared/rootkit_files.txt</rootkit_files>
    <rootkit_trojans>/var/ossec/etc/shared/rootkit_trojans.txt</rootkit_trojans>
    <system_audit>/var/ossec/etc/shared/system_audit_rcl.txt</system_audit>
    <system_audit>/var/ossec/etc/shared/cis_debian_linux_rcl.txt</system_audit>
    <system_audit>/var/ossec/etc/shared/cis_rhel_linux_rcl.txt</system_audit>
    <system_audit>/var/ossec/etc/shared/cis_rhel5_linux_rcl.txt</system_audit>
  </rootcheck>
  
  #<syslog_output>
  #  <server>10.0.0.1</server>
  #  <port>514</port>
  #
  #   Format of alert output. The default format is “default”, or full syslog output.
  #   CEF is the ArcSight Common Event Format.
  #   json can be used with a variety of tools.
  #   The splunk option is for sending data to a Splunk server.
  #   Allowed default, cef, splunk, json
  #  <format>default</format>
  #</syslog_output>

  <active-response>
    <disabled>yes</disabled>
  </active-response>


  <alerts>
    <log_alert_level>1</log_alert_level>
    <email_alert_level>7</email_alert_level>
  </alerts>
  
  <!-- Files to monitor (localfiles) -->
  <localfile>
    <log_format>syslog</log_format>
    <location>/var/log/auth.log</location>
  </localfile>

  <localfile>
    <log_format>syslog</log_format>
    <location>/var/log/syslog</location>
  </localfile>

  <localfile>
    <log_format>syslog</log_format>
    <location>/var/log/dpkg.log</location>
  </localfile>

  <localfile>
    <log_format>apache</log_format>
    <location>/var/log/apache2/error.log</location>
  </localfile>

  <localfile>
    <log_format>apache</log_format>
    <location>/var/log/apache2/access.log</location>
  </localfile>

  <localfile>
    <log_format>command</log_format>
    <command>df -h</command>
  </localfile>

  <localfile>
    <log_format>full_command</log_format>
    <command>netstat -tan |grep LISTEN |grep -v 127.0.0.1 | sort</command>
  </localfile>

  <localfile>
    <log_format>full_command</log_format>
    <command>last -n 5</command>
  </localfile>
</ossec_config>

Agent configuration (Debian)