On Thu, 2009-06-25 at 10:17 -0500, William A. Rowe, Jr. wrote: > André Warnier wrote: > > fredk2 wrote: > >> Would'nt you think that a (simple) timer for the header could fend off > >> some > >> of the effect. Can't we assume that if it takes more than 3 second to > >> enter > >> the header we do not want that client (i'll have to learn to type > >> faster in > >> telnet :-). > >> > > > > For the headers, I think it might help. > > But I'm sure that then the attack would switch to sending the headers > > fast, and then a long POST body, veeeeery slowly... > > > > On another track, it seems that the "Event MPM" model of Apache also is > > relatively insensitive to the slowloris thing. > > ... except, again for POST bodies. Event MPM does not help, there. > It is a bit like an arms race - I guess a solution could be to use a dedicated thread for reading in POST bodies. The best way to stop slowloris is to not allow a single user to cripple your server in this way, by restricting the number of connections a single IP can have to your servers. That of course, only leads to it becoming a DDoS rather than a DoS. Cheers Tom --------------------------------------------------------------------- The official User-To-User support forum of the Apache HTTP Server Project. See <URL:http://httpd.apache.org/userslist.html> for more info. To unsubscribe, e-mail: users-unsubscribe@xxxxxxxxxxxxxxxx " from the digest: users-digest-unsubscribe@xxxxxxxxxxxxxxxx For additional commands, e-mail: users-help@xxxxxxxxxxxxxxxx
|