RE: port 139 syn-fin scans

From: Toby Miller (toby_millerat_private)
Date: Sun Apr 20 2003 - 18:08:45 PDT

  • Next message: Steve Bromwich: "msamba"

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    Been seeing this all day for the past week or so.
    
    					Toby
    
    Hello,
    
    We have been seeing some persistant scanning activity for the past
    week.  When
    we first saw
    it, we thought it was just an isolated incident, but in the last
    couple of
    days we have been
    seeing more of the same thing.
    
    The scans are on TCP port 139 with SYN-FIN flags set and both the
    source and
    destination ports
    set to 139.  The scans attempt to hide by being slow (our /24 gets
    hit roughly
    once every 45 minutes)
    and by using a randomized target address.
    
    We have only seen a couple of source addresses for the probes, but
    they all
    have the same signature.
    Snort reports:
    
    [**] [111:13:1] (spp_stream4) STEALTH ACTIVITY (SYN FIN scan)
    detection [**]
    04/18-00:59:44.192258 aaa.bbb.ccc.ddd:139 -> eee.fff.ggg.hhh:139
    TCP TTL:30 TOS:0x0 ID:39426 IpLen:20 DgmLen:40
    ******SF Seq: 0x1E68EED0 Ack: 0x4B9A8F9A Win: 0x404 TcpLen: 20
    
    
    
    Are any others seeing this ?
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
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