Security Basics mailing list archives
RE: Strange repeating probes to port 80
From: "Paul Jenkins" <pjenkins () dsci com>
Date: Wed, 4 Nov 2009 15:04:44 -0500
Have you checked the whois on the source IP of the offending machine? What is in the packet? -Paul -----Original Message----- From: listbounce () securityfocus com [mailto:listbounce () securityfocus com] On Behalf Of Gleb Paharenko Sent: Friday, October 30, 2009 2:32 PM To: boris mutina Cc: security-basics () securityfocus com Subject: Re: Strange repeating probes to port 80 Hi! IMHO, it might be some botnet command center, which sends UDP probes to check if your host infected. It is interesting in case you resend same UDP packet back :) Here is a clue for UDP managed trojan - it is looking for UDP packets containing word "DOM": http://old.honeynet.org/scans/scan21/sol/scan21_turner.txt 2009/10/26 boris mutina <boris.mutina () gmail com>:
Dear list readers, for unknown reason I decided to create very lame honeypot. I took WXP, enabled IIS and forwarded ports 80 and 135 (both TCP and UDP). Then I started IIS logging and started Wireshark to capture everything on the wire. I was not expecting any special result but what I got is something I cannot explain. From remote host there is a communication request represented by SYN packet to the honeypot port 80. Honeypot responds with SYN/ACK and before it receives ACK, UDP datagram to port 80 is received from that host with payload of length of 19 bytes (sometimes it is 20 or even 21 bytes, dunno why). Then after ACK from remote host TCP data is sent (it appears like HTTP data but it is not), usually with variable length of 20-80 bytes or so. Honeypot sends ACK to this, then there is a 59 seconds delay and then FIN/ACK from remote host followed by ACK and FIN/ACK by honeypot and ACK by remote host. Strange things i cannot explain are these: 1. UDP payload 3rd byte is always 02 2. I tried to connect back to these systems using netcat to the portnumber from which the UDP datagram came from: I tried this: ross@rommy:~$ nc 93.113.XXX.XXX 56856 GET / HTTP/1.0 HTTP/1.0 404 Not Found 3. Tried this: ross@rommy:~$ nc 93.116.XXX.XXX 56856 HEAD / HTTP/1.0 eáÊÃ|Ø(kN|ųDz«n»Íà DÐLq<e4á]ÌÐ %Ax&ߥ[P¾\ª(yVO´ÂËqî ÚØi¿d ò;°aw¼ý sY¶/ 4.Now the most crazy thing is, that these "probes" repeat in relatively precise time interval - 7220 seconds. Can anybody explain me, what the heck is going on? Or am I just chasing a ghost? I can send the data sample upon request. bm ------------------------------------------------------------------------ Securing Apache Web Server with thawte Digital Certificate In this guide we examine the importance of Apache-SSL and who needs an SSL certificate. We look at how SSL works, how it benefits your company and how your customers can tell if a site is secure. You will find out how to test, purchase, install and use a thawte Digital Certificate on your Apache web server. Throughout, best practices for set-up are highlighted to help you ensure efficient ongoing management of your encryption keys and digital certificates. http://www.dinclinx.com/Redirect.aspx?36;4175;25;1371;0;5;946;e13b6be442f727d1 ------------------------------------------------------------------------
-- Best regards. Gleb Pakharenko. http://gpaharenko.livejournal.com http://www.linkedin.com/in/gpaharenko +380503116172 ------------------------------------------------------------------------ Securing Apache Web Server with thawte Digital Certificate In this guide we examine the importance of Apache-SSL and who needs an SSL certificate. We look at how SSL works, how it benefits your company and how your customers can tell if a site is secure. You will find out how to test, purchase, install and use a thawte Digital Certificate on your Apache web server. Throughout, best practices for set-up are highlighted to help you ensure efficient ongoing management of your encryption keys and digital certificates. http://www.dinclinx.com/Redirect.aspx?36;4175;25;1371;0;5;946;e13b6be442f727d1 ------------------------------------------------------------------------ ------------------------------------------------------------------------ Securing Apache Web Server with thawte Digital Certificate In this guide we examine the importance of Apache-SSL and who needs an SSL certificate. We look at how SSL works, how it benefits your company and how your customers can tell if a site is secure. You will find out how to test, purchase, install and use a thawte Digital Certificate on your Apache web server. Throughout, best practices for set-up are highlighted to help you ensure efficient ongoing management of your encryption keys and digital certificates. http://www.dinclinx.com/Redirect.aspx?36;4175;25;1371;0;5;946;e13b6be442f727d1 ------------------------------------------------------------------------
Current thread:
- RE: Strange repeating probes to port 80 Paul Jenkins (Nov 09)