cipherdyne.org

Michael Rash, Security Researcher



Chapter 6: psad Operations: Detecting Suspicious Traffic

There are many features offered by psad, and these features are designed to maximize your use of iptables log messages. From port scans to probes for backdoors, psad detects and reports suspicious activity with verbose email and syslog alerts.

Here is an example psad alert:
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         Danger level: [4] (out of 5)

    Scanned TCP ports: [10-65301: 1522 packets]
            TCP flags: [SYN: 1522 packets, Nmap: -sT or -sS]
       iptables chain: INPUT (prefix "DROP"), 499 packets

               Source: 192.168.10.200
                  DNS: int_scanner
             OS guess: Linux:2.5::Linux 2.5 (sometimes 2.4)

          Destination: 192.168.10.1
                  DNS: iptablefw

   Overall scan start: Thu Sep 13 21:22:26 2007
   Total email alerts: 7
   Complete TCP range: [1-65301]
      Syslog hostname: iptablesfw

         Global stats: chain:   interface:   TCP:   UDP:   ICMP:  
                       INPUT    eth1         3229   0      2      


[+] TCP scan signatures:

   "BACKDOOR SatansBackdoor.2.0.Beta, or BackConstruction 2.1 Connection Attempt"
       dst port:  666 (no server bound to local port)
       flags:     SYN
       psad_id:   100041 (derived from: 118 157 158)
       chain:     INPUT
       packets:   2
       classtype: misc-activity
       reference: (arachnids) http://www.whitehats.com/info/IDS316

   "POLICY vncviewer Java applet communication attempt"
       dst port:  5801 (no server bound to local port)
       flags:     SYN
       sid:       1846
       chain:     INPUT
       packets:   1
       classtype: misc-activity
       reference: (nessus) http://cgi.nessus.org/plugins/dump.php3?id=10758

   "P2P Napster Client Data communication attempt"
       dst port:  6699 (no server bound to local port)
       flags:     SYN
       sid:       561
       chain:     INPUT
       packets:   2
       classtype: policy-violation

   "SNMP AgentX/tcp request"
       dst port:  705 (no server bound to local port)
       flags:     SYN
       sid:       1421
       chain:     INPUT
       packets:   2
       classtype: attempted-recon
       reference: (bugtraq) http://www.securityfocus.com/bid/4088
       reference: (bugtraq) http://www.securityfocus.com/bid/4089
       reference: (bugtraq) http://www.securityfocus.com/bid/4132
       reference: (cve) http://cve.mitre.org/cgi-bin/cvename.cgi?name=2002-0012
       reference: (cve) http://cve.mitre.org/cgi-bin/cvename.cgi?name=2002-0013


[+] Whois Information:

OrgName:    Internet Assigned Numbers Authority 
OrgID:      IANA
Address:    4676 Admiralty Way, Suite 330
City:       Marina del Rey
StateProv:  CA
PostalCode: 90292-6695
Country:    US

NetRange:   192.168.0.0 - 192.168.255.255 
CIDR:       192.168.0.0/16 
NetName:    IANA-CBLK1
NetHandle:  NET-192-168-0-0-1
Parent:     NET-192-0-0-0-0
NetType:    IANA Special Use
NameServer: BLACKHOLE-1.IANA.ORG
NameServer: BLACKHOLE-2.IANA.ORG
Comment:    This block is reserved for special purposes.
Comment:    Please see RFC 1918 for additional information.
Comment:    
RegDate:    1994-03-15
Updated:    2002-09-16

OrgAbuseHandle: IANA-IP-ARIN
OrgAbuseName:   Internet Corporation for Assigned Names and Number 
OrgAbusePhone:  +1-310-301-5820
OrgAbuseEmail:  abuse@iana.org

OrgTechHandle: IANA-IP-ARIN
OrgTechName:   Internet Corporation for Assigned Names and Number
OrgTechPhone:  +1-310-301-5820
OrgTechEmail:  abuse@iana.org

# ARIN WHOIS database, last updated 2007-09-15 19:10
# Enter ? for additional hints on searching ARIN's WHOIS database.

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