Ethical Hacking Learn to find vulnerabilities before the bad guys do! Gain real world hands on hacking experience in our state of the art hacking lab. Course designed and taught by expert instructors with years of penetration testing experience. 12 student maximum in every class. Certification attempt included in every package. | Computer Forensics Training at InfoSec Institute Gain the in-demand skills of a certified computer examiner, learn to recover trace data left behind by fraud, theft, and cybercrime perpetrators. Discover the source of computer crime and abuse at your organization so that it never happens again. All of our class sizes are guaranteed to be 12 students or less to facilitate one-on-one interaction with one of our expert instructors. |

| Subject: | Re: [Snort-sigs] False negatives on "ATTACK-RESPONSES id check returned userid" |
|---|---|
| Date: | Fri, 4 May 2007 09:45:09 +0200 |
Looks good to me!
On Mon, Apr 16, 2007 at 12:40:27PM +0200, Cees wrote: > Some additional information: > > Version of snort used: 2.6.1.2 > Snort.conf configuration: > var HOME_NET [192.168.247.133/32] > var EXTERNAL_NET !$HOME_NET > [..] > Preprocessors: frag3, stream4, http_inspect > > Command-line options when starting snort: > snort -u snort -r uid.pcap -l log/ -c snort.conf > > Operating system used: Gentoo linux > > Attached a sample PCAP file. A client (192.168.247.129) retrieves a website > from the server (192.168.247.133) with the string "uid=33(www-data) > gid=33(www-data) groups=33(www-data)".
I seem to recall discussion about this rule and its potential for false-negatives sometime in the past. The further you crank out 'within', the greater the chance of a false-positive. There is definitely room for improvement, IMO, as uid and gid combinations that are greather than 9 characters in length are quite common.
Why not pcre for this rule? 'pcre:/uid=\d+\S+\s+gid=\d+\S+'?
-jon
------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/
_______________________________________________ Snort-sigs mailing list Snort-sigs@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/snort-sigs
| <Prev in Thread] | Current Thread | [Next in Thread> |
|---|---|---|
| ||
| Previous by Date: | [Snort-sigs] Bleeding Edge Threats Daily Signature Changes, bleeding |
|---|---|
| Next by Date: | [Snort-sigs] Bleeding Edge Threats Daily Signature Changes, bleeding |
| Previous by Thread: | [Snort-sigs] new rule for detect Apple QTJava toQTPointer() access, rmkml |
| Next by Thread: | [Snort-sigs] Bleeding Edge Threats Weekly Signature Changes, bleeding |
| Indexes: | [Date] [Thread] [Top] [All Lists] |