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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: 80/udp floods?
Wayne E. Bouchard wrote: We've seen >1Gb/s connection filling attacks from ARIN space, especially 24.x blocks.Yes, this seems to be a common thing these days. You send udp/LAGE udp packets and fragments to port 80 to saturate bandwidth and you combine that with compromised hosts successively opening and closing TCP connections to port 80 (Not a syn flood, actual connections that look to the router in terms of packet size etc to be legitimate.) A note that the majority of these hosts are from LACNIC and APNIC space. (with a smattering from RIPE) I almost never see ARIN address space used for these compromised hosts. Most of the attacks I've seen recently have used this setup. Easy enough to fend off except for the TCP 80 bit. For most of these attacks, I've taken to just filtering the entire LACNIC and APNIC address delegations at the host level for the durration of the incident since, in the general case, my customers (the ones that suffer these incidents) do little if any business in that region. FYI, Deepak Jain AiNET
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