Security Incidents mailing list archives
Re: TCP Src 5635: what is it?
From: Scott Nursten <scott.nursten () StreetsOnline co uk>
Date: Thu, 12 Jul 2001 09:58:30 +0100
Yeah, definitely a scan. Snort detects it as an NMAP XMAS scan, but in reality, it could be any packet crafting tool
(nemisis, hping2 or nmap).
Heres a sample packet that's hit my IDS with a SRC PORT of 5635:
-----------------
#(1 - 8041) [2001-07-10 18:50:38] NMAP XMAS scan
IPv4: 212.111.188.176 -> 194.130.109.65
hlen=5 TOS=0 dlen=106 ID=64773 flags=0 offset=0 TTL=111 chksum=19876
TCP: port=5635 -> dport: 0 flags=**U*P**F seq=1359020032
ack=1292042247 off=0 res=2 win=43093 urp=9716 chksum=7155
Payload: length = 66
000 : 40 CC C6 34 62 66 E0 DF FF 1D 86 BE 4E F6 BF 60 @..4bf......N..`
010 : 70 95 33 11 C9 1A 0F 20 AB 63 27 36 F1 C9 D4 D3 p.3.... .c'6....
020 : B9 00 DC 4F 44 E1 83 25 AB 47 7D 20 CB DB EE BC ...OD..%.G} ....
030 : 42 9C 21 BE 5C 95 1B A2 00 06 00 03 00 08 00 06 B.!.\...........
040 : 01 00 ..
-----------------
Rgds,
Scott
Curt Purdy wrote:
IMO, this looks like an hping2 scan. See http://project.honeynet.org/scans/arch/scan1.txt for a sample honeynet scan that is just the opposite (dest 0 - src high port). But as they explain, the default hping2 is actually (scr 0 - dest high port) as in your case. Curt Purdy Information Systems Engineer DP Solutions -----Original Message----- From: rlt () subdimension com [mailto:rlt () subdimension com] Sent: Tuesday, July 10, 2001 10:11 AM To: incidents () securityfocus com Subject: TCP Src 5635: what is it? Just a little help needed here. I've been seeing a lot of traffic with a source port of 5635 and a destination port of 0. Searching on google yields no significant results. There were two forums that asked the same question and haven't yet gotten an answer. I asked the posters for more information and if there problems had been resolved but I haven't gotten a response yet. So, any help and or insight would be much appreciated. Here's an excerpt from my logs: Time,Source Addr,Source Port,Dest Addr,Dest Port,TCP/UDP,TCP Flags ,,,,,, 6/28/01 15:41,208.33.170.61 (cvxp061.intrstar.net),5635,Host.In.Our.DMZ,0,TCP, 6/28/01 15:41,208.33.170.61 (cvxp061.intrstar.net),5635,Host.In.Our.DMZ,0,TCP,fin rst psh 6/28/01 16:55,63.254.34.74 (A010- 0074.FRDK.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,syn psh 6/28/01 17:50,208.33.170.154 (cvxp154.intrstar.net),5635,Host.In.Our.DMZ,0,TCP,rst 6/29/01 0:04,63.252.82.9 (A010- 0009.FTVL.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,fin syn rst psh ack urg 6/29/01 0:04,63.252.82.9 (A010- 0009.FTVL.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,syn rst 6/29/01 0:04,63.252.82.9 (A010- 0009.FTVL.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,rst urg 6/29/01 7:26,63.255.89.15 (A010- 0015.HIPT.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,fin syn rst urg 6/29/01 7:26,63.255.89.15 (A010- 0015.HIPT.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,fin syn rst urg 6/29/01 7:26,63.255.89.15 (A010- 0015.HIPT.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,fin syn rst urg 6/29/01 7:26,63.255.89.15 (A010- 0015.HIPT.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,fin syn rst urg 6/29/01 7:26,63.255.89.15 (A010- 0015.HIPT.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,fin syn rst urg 6/29/01 7:27,63.255.89.15 (A010- 0015.HIPT.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,fin syn rst urg 6/29/01 7:28,63.255.89.15 (A010- 0015.HIPT.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,psh urg 6/29/01 7:34,209.156.206.217 (A020- 0979.GNBO.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,syn rst urg 6/29/01 7:34,209.156.206.217 (A020- 0979.GNBO.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,syn rst urg 6/29/01 7:34,209.156.206.217 (A020- 0979.GNBO.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,syn rst urg 6/29/01 7:34,209.156.206.217 (A020- 0979.GNBO.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,syn rst urg 6/29/01 7:35,209.156.206.217 (A020- 0979.GNBO.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,syn rst urg 6/29/01 7:35,209.156.206.217 (A020- 0979.GNBO.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,syn rst urg 6/29/01 7:35,209.156.206.217 (A020- 0979.GNBO.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,syn rst urg 6/29/01 7:35,209.156.206.217 (A020- 0979.GNBO.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,syn rst urg 6/29/01 7:35,209.156.206.217 (A020- 0979.GNBO.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,syn rst urg 6/29/01 7:35,209.156.206.217 (A020- 0979.GNBO.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,syn rst urg 6/29/01 7:35,209.156.206.217 (A020- 0979.GNBO.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,fin syn rst urg 6/29/01 7:35,209.156.206.217 (A020- 0979.GNBO.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,fin syn rst urg 6/29/01 7:35,209.156.206.217 (A020- 0979.GNBO.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,fin syn rst urg 6/29/01 7:35,209.156.206.217 (A020- 0979.GNBO.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,fin syn rst urg 6/29/01 7:35,209.156.206.217 (A020- 0979.GNBO.splitrock.net),5635,Host.In.Our.DMZ,0,TCP,fin syn rst urg The TCP flags are varied. I know it's not indicated here but I didn't want to send the entire list of attempts. There server that these IP's are destined for happens to be a HTTPS server. And these IP's have also established full connections with the server. So I'm not sure if this is an attack or some wacky software mis- configuration. Again, any help and or insight would be appreciated. Thanks in advance. -Rick -------------------------------------- FREE ANONYMOUS EMAIL! Sign up now. http://www.subdimension.com/freemail ---------------------------------------------------------------------------- This list is provided by the SecurityFocus ARIS analyzer service. For more information on this free incident handling, management and tracking system please see: http://aris.securityfocus.com ---------------------------------------------------------------------------- This list is provided by the SecurityFocus ARIS analyzer service. For more information on this free incident handling, management and tracking system please see: http://aris.securityfocus.com
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Scott Nursten - Systems Administrator
Streets Online Ltd.
Direct: +44 (0) 1293 744 122
Business: +44 (0) 1293 402 040
Fax: +44 (0) 1293 402 050
Email: scottn () streetsonline co uk
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Current thread:
- TCP Src 5635: what is it? rlt (Jul 10)
- RE: TCP Src 5635: what is it? Curt Purdy (Jul 10)
- Re: TCP Src 5635: what is it? Scott Nursten (Jul 12)
- RE: TCP Src 5635: what is it? Curt Purdy (Jul 10)