Snort mailing list archives
Re: DNS Zone Transfer False Positive
From: James Hoagland <jim () SiliconDefense com>
Date: Wed, 26 Mar 2003 08:45:39 -0800
Ron, What exact snort version are you using?Also, any change we can get a hex dump of the TCP payload? E.g., snort's text pretty-printing or tcpdump -X.
Thanks, Jim At 10:25 AM -0600 3/26/03, Ron Shuck wrote:
Hi, I have been getting a few DNS Zone Transfer false positives. They originate from 2K or XP workstations. When I examined a little closer, it appeared to be a DNS query containing a TSIG. The signature portion of the TSIG additional record contains the content string from the snort signature |00 00 FC|. Anyone have any ideas of how to eliminate this type of false positive from the signature? I would also appreciate any explanation what the heck this traffic does? I am just looking into rfc2931 and 2535. Transmission Control Protocol, Src Port: 2856 (2856), Dst Port: domain (53), Seq: 3389545719, Ack: 3366544751, Len: 273 Domain Name System (query) Length: 271 Transaction ID: 0xcf88 Flags: 0x0000 (Standard query) 0... .... .... .... = Response: Message is a query .000 0... .... .... = Opcode: Standard query (0) .... ..0. .... .... = Truncated: Message is not truncated .... ...0 .... .... = Recursion desired: Don't do query recursively .... .... ...0 .... = Non-authenticated data OK: Non-authenticated data is unacceptable Questions: 1 Answer RRs: 1 Authority RRs: 0 Additional RRs: 1 Queries 9XXXXXXXXXXX-3: type TKEY, class inet Name: 9XXXXXXXXXXX-3 Type: Transaction Key Class: inet Answers 9XXXXXXXXXXX-3: type TKEY, class any Name: 9XXXXXXXXXXX-3 Type: Transaction Key Class: any Time to live: 0 time Data length: 136 Algorithm name: gss.microsoft.com Signature inception: Mar 3, 2003 08:01:36.000000000 Signature expiration: Mar 4, 2003 08:01:36.000000000 Mode: GSSAPI Error: No error Key Other Additional records 9XXXXXXXXXXX-3: type TSIG, class any Name: 9XXXXXXXXXXX-3 Type: Transaction Signature Class: any Time to live: 0 time Data length: 51 Algorithm name: gss.microsoft.com Time signed: Mar 3, 2003 08:01:36.000000000 Fudge: 36000 Signature Original id: 53128 Error: No error Other Best Regards, Ron Shuck, CISSP - Managing Consultant Buchanan Associates - A Technology Company in the People Business http://www.buchanan.com http://www.isc2.org Content-Type: application/x-pkcs7-signature; name="smime.p7s" Content-Disposition: attachment; filename="smime.p7s" Attachment converted: Shu:smime 15.p7s (????/----) (00120A70)
-- |* Jim Hoagland, Associate Researcher, Silicon Defense *| |* --- Silicon Defense: The Cyberwar Defense Company --- *| |* jim () SiliconDefense com, http://www.silicondefense.com/ *| |* Voice: (530) 756-7317 Fax: (530) 756-7297 *| ------------------------------------------------------- This SF.net email is sponsored by: The Definitive IT and Networking Event. Be There! NetWorld+Interop Las Vegas 2003 -- Register today! http://ads.sourceforge.net/cgi-bin/redirect.pl?keyn0001en _______________________________________________ Snort-users mailing list Snort-users () lists sourceforge net Go to this URL to change user options or unsubscribe: https://lists.sourceforge.net/lists/listinfo/snort-users Snort-users list archive: http://www.geocrawler.com/redir-sf.php3?list=snort-users
Current thread:
- DNS Zone Transfer False Positive Ron Shuck (Mar 26)
- Re: DNS Zone Transfer False Positive James Hoagland (Mar 26)
- <Possible follow-ups>
- RE: DNS Zone Transfer False Positive Geoff Craig (Mar 26)
- RE: DNS Zone Transfer False Positive Ron Shuck (Mar 26)
- RE: DNS Zone Transfer False Positive James Hoagland (Mar 27)
- RE: DNS Zone Transfer False Positive Geoff Craig (Mar 26)