26th Sep 2002 [SBWID-5264]
COMMAND
snort bypass using fragroute
SYSTEMS AFFECTED
All versions
PROBLEM
0xcafebabe reported a post by Dug Song, which released a tool on the
focus-ids list which totally blindsides Snort :
http://www.monkey.org/~dugsong/fragroute/index.html
His README.snort file contains several fragroute scripts which
blindside even the current Snort version in CVS, tested on RedHat 7.2.
For example, the latest wu-ftpd exploits run through the one line
"tcp_seg 1 new" don't trigger any Snort alerts at all.
SOLUTION
Update (25 April 2002)
======
Snort 1.8.7beta1 is available at :
http://www.snort.org/dl/beta/snort-1.8.7beta1.tar.gz.
This should correct the issues that fragroute induces.