RE: port 139 syn-fin scans

["Toby Miller" <toby_miller () adelphia net>]

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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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