Security Incidents mailing list archives
RE: SYN FIN Scan with src port == dst port
From: "Fernando Cardoso" <fernando.cardoso () whatevernet com>
Date: Wed, 20 Jun 2001 09:19:28 +0100
Hi Nicolas
here some logs from probes done by compromised boxes. The first one (hacked_1) is a default RedHat 6.2 and the second one (hacked_2) is a default Cobalt 5.0 Admins have been notified. Jun 17 21:23:22 my_box_1 snort[468]: SCAN-SYN FIN: hacked_1:511 -> my_box_1:511 Jun 17 21:23:22 my_box_2 snort[5207]: SCAN-SYN FIN: hacked_1:511 -> my_box_2:511
[...] .
Every packet have the same values for a few fields : TOS:0x0 ID:39426 IpLen:20 DgmLen:40 Win: 0x404 TcpLen: 20 Have you ever seen that ?
Everytime :) This is for sure a synscan probe. It has all the symptoms: source port=destination port, ID=39426 and Window=404. If you were using the Whitehats signatures for Snort you would find a rule for that sort of scan. Cheers Fernando -- Fernando Cardoso - Security Consultant WhatEverNet Computing, S.A. Phone : +351 21 7994200 Praca de Alvalade, 6 - Piso 6 Fax : +351 21 7994242 1700-036 Lisboa - Portugal email : fernando.cardoso () whatevernet com http://www.whatevernet.com/ _____________________________________________________________________ INTERNET MAIL FOOTER A presente mensagem pode conter informação considerada confidencial. Se o receptor desta mensagem não for o destinatário indicado, fica expressamente proibido de copiar ou endereçar a mensagem a terceiros. Em tal situação, o receptor deverá destruir a presente mensagem e por gentileza informar o emissor de tal facto. --------------------------------------------------------------------- Privileged or confidential information may be contained in this message. If you are not the addressee indicated in this message, you may not copy or deliver this message to anyone. In such case, you should destroy this message and kindly notify the sender by reply email. ---------------------------------------------------------------------
Current thread:
- SYN FIN Scan with src port == dst port Nicolas Gregoire (Jun 19)
- RE: SYN FIN Scan with src port == dst port Fernando Cardoso (Jun 20)
- Synscan on port 2223 Fernando Cardoso (Jun 26)
- Re: Synscan on port 2223 Daniel Martin (Jun 27)
- Synscan on port 2223 Fernando Cardoso (Jun 26)
- RE: SYN FIN Scan with src port == dst port Fernando Cardoso (Jun 20)