The following Denial of Service Flaw was reported in Samba 3.0 versions prior to and including v3.0.6:

(i) A DoS bug in smbd may allow an unauthenticated user to cause smbd to spawn new processes each one entering an infinite 

loop. After sending a sufficient amount of packets it is possible to exhaust the memory resources on the server. 
(ii) A DoS bug in nmbd may allow an attacker to remotely crash the nmbd daemon. 

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