Re: Logs: Many hits with source port of 80

From: Valdis.Kletnieksat_private
Date: Mon Dec 16 2002 - 08:01:45 PST

  • Next message: Russell Fulton: "Re: Logs: Many hits with source port of 80"

    On Fri, 13 Dec 2002 10:05:56 GMT, Byrne Ghavalas <securityat_private>  said:
    > Has anyone else noticed a high number of hits in their security logs,
    > where the source port is set to tcp 80 and the destination port is some
    > high tcp port? I have noticed that these events seem to be getting more
    > numerous than the NetBios scans ;-)
    > 
    > For example:
    > 2002-12-13 09:08:04 194.78.225.36:80 XX.XX.XX.XX:29439
    
    The analysis differs considerably depending on whether these were SYN packets,
    or SYN+ACK. If they're SYN packets *from* 80, that's odd in one way - however a
    SYN+ACK would probably indicate either backscatter from a DDoS where somebody
    used your IP as a forged source address, or that you were having a nice burn of
    some worm on your internal net, and they were all trying to phone home..
    
    
    -- 
    				Valdis Kletnieks
    				Computer Systems Senior Engineer
    				Virginia Tech
    
    
    
    



    This archive was generated by hypermail 2b30 : Wed Dec 18 2002 - 18:18:55 PST