Is SYN flooding still a threat?

Posted by Rob on Server Fault See other posts from Server Fault or by Rob
Published on 2010-05-15T23:55:12Z Indexed on 2010/05/16 0:01 UTC
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tcp

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rst

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denial-of-service

Well recently I've been reading about different Denial of Service methods. One method that kind of stuck out was SYN flooding. I'm a member of some not-so-nice forums, and someone was selling a python script that would DoS a server using SYN packets with a spoofed IP address.

However, if you sent a SYN packet to a server, with a spoofed IP address, the target server would return the SYN/ACK packet to the host that was spoofed. In which case, wouldn't the spoofed host return an RST packet, thus negating the 75 second long-wait, and ultimately failing in its attempt to DoS the server?

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