
YuChakTinMichael‘sGIACGCFWProjectAssignment
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DoSattack
TheDoSattackthatIwilluseisaSmurfattack.AccordingtoSymantec,Smurfattack
isaformofDoSthatusesping:
“In thecaseofaSmurfDoSattack,theping'spacketreturnIPaddressisforgedwith
theIPofthetargetedmachine. ThepingisissuedtotheentireI Pbroadcastaddress.
Thiscauseseverymachinetorespondtotheboguspingpacketsandreplytothe
targetedmachine,whichfloodsit.ThisiscalledaSmurfattackbecausetheDoStool
usedtoperformtheattackiscalledSmurf.”
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Asdescribedby pentics.net,
“Therearetwopartieswhoarehurt bythisattack... theintermediary(broadcast)
deviceslet'scallthem"amplifiers",andthespoofedaddresstarget,orthe"victim".
Thevictimisthetargetofalargeamountoftrafficthattheamplifiersgenerate.”70
Sincewehave50compromisedDSLsystemsatourdisposal,anattackofa
reasonablestrengthcanbelaunched.Theroleofthesecompromisedsystemswillbe
discussedshortly.
TheAmplifiers
Whocanactasamplifier?
Basically,anynetworkwithroutersacceptingIPdirectedbroadcastandhosts
acceptingICMPpacketscanbeusedasamplifiers.
Howdowelocatetheseamplifiers?
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http://www.symantec.com/avcenter/venc/data/smurf.dos.attack.html
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http://www.pentics.net/denialofservice/whitepapers/smurf.cgi
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