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New Member

udp port 0

i have notice that one of our nodes UNIX server is sending udp packets to many nodes on the internet and the nodes are replying back to the server using udp packets. this consume about 512kbps , and the attack is into port 0 (udp port 0). we have implement access-list to deny the udb into port 0 , but it didnt work????, can the router deny udp port 0 , if not , how can i solve such a problem. thx

3 REPLIES
Cisco Employee

Re: udp port 0

it could be UDP port denial-of-service attack, disable the following chargen services on your router in config mode;

no service udp-small-servers

no service tcp-small-servers

HTH

R/Yusuf

New Member

Re: udp port 0

thx yusuff, i already did that , but it still dont work , i still recieve the udp port0 .

any suggestions

Cisco Employee

Re: udp port 0

hmmmm.....

could you also turn off the following

no service finger

no ip bootp server

also give the show process output, do we see lot of processes with the same name, for example, "UDP Echo."

R/Yusuf

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