types and DOS attack & basics of denial of service.pdf

CF

1. DoSAttacks
Basics

2. OUTLINE
•What Is DoS and what is DoS Attack
•History
•Types of Attacks
•Main targets today
•How to Defend
•Prosecution
•Conclusion

3. WHAT IS “DOSATTACK”
Denial-Of-ServiceAttack=DOSAttackisamaliciousattemptbya
singlepersonoragroupofpeopletocausethevictim,siteor
nodetodenyservicetoitcustomers.
•DoS=whenasinglehostattacks
•DDoS=whenmultiplehostsattacksimultaneously

4. IDEA OF “DOSATTACKS”
•Purposeistoshutdownasite,notpenetrateit.
•Purposemaybevandalism,extortionorsocialaction
(includingterrorism)(Sportsbettingsitesoftenextorted)
•Modificationofinternaldata,changeofprograms(Includes
defacementofwebsites)

5. Denial of Service Attack
Typical Connection

6. HISTORY
Morris Worm (November 2, 1988)
•First DDoS attack to cripple large amounts of network
infrastructure
•Self-replicating, self-propagating.
•Exploited software commonality (monoculture)
1.Fingerd buffer overflow exploit
2.Sendmail root vulnerability
3.Weak passwords

7. HISTORY
Morris Worm effect
•Infectedsystemsbecame“catatonic”
•Tookroughlythreedaystocomeundercontrol
•Ultimatelyinfected10%ofInternetcomputers(6,000)and
cost$milliontocleanup.
•Morrisconvictedundercomputerfraudandabuseact,three
yearsprobation,fineof$10,000

8. TYPES OF DOSATTACKS

9. TYPES OF DOSATTACKS
•Penetration
•Eavesdropping
•Man-In-The-Middle
•Flooding

10. TYPES OF DOSATTACKS
Penetration
•Attackergetsinsideyourmachine
•Cantakeovermachineanddowhateverhewants
•Achievesentryviasoftwareflaw(s),stolenpasswords
orinsideraccess

11. TYPES OF DOSATTACKS
Eavesdropping
•Attacker gains access to same network
•Listens to traffic going in and out of your machine

12. TYPES OF DOSATTACKS
Man-in-the-Middle
•Attacker listens to output and controls output
•Can substitute messages in both directions

13. TYPES OF DOSATTACKS
Flooding
•Attackersendsanoverwhelmingnumberofmessagesatyour
machine;greatcongestion
•Thecongestionmayoccurinthepathbeforeyourmachine
•Messagesfromlegitimateusersarecrowdedout
•UsuallycalledaDenialofService(DoS)attack,becausethat’s
theeffect.
•Usuallyinvolvesalargenumberofmachines,hence
DistributedDenialofService(DDoS)attack

14. MAIN TARGETS

15. HOW TO DEFEND
•Firewalls-can effectively prevent users from launching simple
flooding type attacks from machines behind the firewall.
•Switches-Some switches provide automatic and/or system-
widerate limiting,traffic shaping,delayed bindingto detect
and remediate denial of service attacks
•Routers-If you add rules to take flow statistics out of the
router during the DoS attacks, they further slow down and
complicate the matter
•DDS based defense
•Clean pipes

16. •Nothing can be done to entirely prevent DOS
•Minimize the dangers
–Effective and Robust Design
–Bandwidth Limitations
–Keep Systems Patched
–Run the least amount of services
–Allow only necessary traffic
–Block IP addresses

17. CONCLUSION
•Roleofinternationalboundaries-consoleslocatedacross
internationalborders,law-enforcementproblem
•Inthepast,asthepresent,DDoShasbeenmoreanuisance
activityconductedbycybervandalsthananactivitywith
specificsocioeconomicaims
•Inthefuture,DDoSmaybeusedasadisruptiveforce,with
broaddestabilizationasitsaiminsteadofthetargetingof
specifictargets
•Destabilizationhasahigh(ROI)ReturnOnInvestmentwhen
comparedtotargetedattacks

18. THANK YOU