COMMAND
RemoteAdmin/AOL Server 2.2
SYSTEMS AFFECTED
Unix Servers Running AOL Server 2.2
PROBLEM
Following info is based on Rhino9 Advisory #1. Any local user is
able to retrieve the encrypted password of the AOLserver's
nsdadmin account, the password system uses DES, so the attacker
can crack the password using the appropriate software. This is
because the nsd.ini file, which AOLserver uses to set up it's port
settings and other characteristics, is world-readable. The
nsadmin account can be compromised and then used to modify the
AOLserver configuration, change passwords or shutdown the server.
Once a local user has cracked the password, he is then able to use
a web browser to reconfigure the server by visiting the following
URL:
http://host.to.attack.com:9876/NS/Setup
Here we use port 9876 because it was defined in the nsd.ini file
as:
[ns/setup] Port=9876.
Once at the password prompt, the attacker simply enters the
nsadmin username and the password that he cracked. The attacker
now has complete control over the AOLserver. To exploit this,
you must first locally locate the AOLserver directory
(find / -name nsd.ini), and follow these simple steps:
% cd <AOLserver directory>
% grep Password nsd.ini
Password=t2GU5GN5XJWvk
%
Next, crack the DES encrypted string using your favorite cracker
program.
SOLUTION
Make the nsd.ini file readable only by it's owner.