COMMAND
ColdFusion
SYSTEMS AFFECTED
ColdFusion Web Application Server (Windows NT, Solaris, HP-UX) up through and including 4.5.1.
PROBLEM
Following is based on Security Advisory by Allaire's ColdFusion.
A denial of service vulnerability exists within the Allaire
ColdFusion web application server which allows an attacker to
overwhelm the web server and deny legitimate web page requests.
The problem lies within the ColdFusion mechanism that manages the
parsing of passwords within authentication requests. This problem
makes the ColdFusion Administrator login page vulnerable to a
denial of service attack. The denial of service occurs during
the process of converting the input password and the stored
password into forms suitable for comparison when the input
password is very large (>40,000 characters).
For proof of concept use the well-known HTML tag field overflow
technique to overflow the HTML password field on the Administrator
login page:
http://vulnerable.server.here/cfide/administrator/index.cfm
The attacker simply changes the field size and POST action in the
HTML tags on the page to allow a large string (over 40,000
characters) to be submitted to the ColdFusion server. Small input
strings may not immediately crash the system but large enough
strings will bring the system to a halt.
SOLUTION
Allaire provides the following workaround: Customers should back
up all existing data and implement the recommendations made in the
article, 'Securing the ColdFusion Administrator (10954)'. This
should resolve the issue. The article can be found at
http://www.allaire.com/Handlers/index.cfm?ID=10954&Method=Full
A fix is expected in the future release of ColdFusion 4.6
(Q4,2000).