COMMAND
Surge FTP Server
SYSTEMS AFFECTED
Surge FTP Server 2.0a
PROBLEM
Following is based on a ID0301061701 advisory provided by Sentry
Research Labs by Siberian. Surge FTP Server is a US$385 FTP
Server Software from Netwin, which come with serveral features
like webinterface and other intresting features
Issue:
1.) A simple directory transversal bug allows listing of normaly
unaccessable files
2.) FTP allows anybody to DOS the machine with a well known
con/con attack.
Exploit:
1.) Connect to the server with anonymous and type "nlist ..."
2.) Connect to the server with anonymous and type cd con/con (yes,
this is well know and works with MANY other too, but we think
it should be filtered).
CON/CON is easy to avoid - you just filter on CON/CON. But then
you also have to consider _every_ other DOS device name (MS calls
them DDNs, in KB articles that reference them) that is, or could
be, on your system. CLOCK$, for instance, can be used instead of
CON, as can AUX, PRN, LPT1-9, etc, etc.
SOLUTION
Update to ver 2.0b available form www.netwinsite.com/surgeftp.