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Date: Sat, 21 Feb 1998 22:58:42 EST From: Mark M Marko <john__wayne@JUNO.COM> To: BUGTRAQ@NETSPACE.ORG Subject: FoolProof Insecurities Howdy, I have found a weakness in the password impelementation of FoolProof. FoolProof is a software package used to secure workstations and LAN client machines from DoS and other lame-ass attacks by protecting system files (autoexec.bat, config.sys, system registry) and blocking access to specified commands and control panels. FoolProof was written by Smart Stuff software originally for the Macintosh but recently released for win3.x and win95. All my information pertains directly to versions 3.0 and 3.3 of both the 3.x and 95 versions but should be good for all early versions if they exist. Since my high school bought a sight licence I have spent some time playing with it. It is capable of modifying the boot sequence on win3.x machines to block the use of hot keys and prevent users from breaking out of autoexec. It also modifies the behavior of command.com so that commands can be verified by a database and anything deemed unesseccary or potentially malicio f44 us can be blocked (fdisk, format, dosshell?, dir, erase, del. defrag, chkdsk, defrag, undelete, debug, etc.). Its windows clients provide for a way to log into/out of FoolProof for privilaged access by using a password or hot key assignment. The newer instalation of 95 machines have a centralized configuration database that lives on our NetWare server. My first success with breaking FoolProof passwords came by using a hex editor to scan the windows swap file for anything that might be of interested. In the swap file I found the password in plain text. I was surprised but thought that it was something that would be simply unavoidable and unpredictable. Later though I used a memory editor on the machine (95 loves it when I do that) and found that FoolProof stores a copy of the user password IN PLAIN TEXT inside its TSR's memory space. To find a FoolProof password, simply search through conventional memory for the string "FOOLPROO" (I don't knowwhat they did with that last "F") and the next 128 bytes or so should contain two plaintext passwords followed by the hot-key assignment. For some reason FoolProof keeps two passwords on the machine, the present one and a 'legacy' password (the one you used before you _thought_ it was changed). There exist a few memory viewers/editors but it isn't much effort to write something. Getting to a point where you can execute something can be difficult but isn't impossible. I found that it is more difficult to do this on the win3.x machines because FoolProof isn't compromised by the operating system it sits on top of; basicly getting a dos prompt is up to you (try file manager if you can). 95 is easier because it is very simple to convince 95 that it should start up into Safe-Mode and then creating a shortcut in the StartUp group to your editor and then rebooting the machine (FoolProof doesn't get a chance to load in safe mode). I tried to talk to someone at SmartStuff but they don't seem to care what trouble their simple minded users might get into. They told me I must be wrong because they use 128 bit encryption on the disk. Apparently they don't even know how their own software works because the utility they provide to recover lost passwords requires some 32+ character master password that is hardwired into each installation. JohnWayne _____________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com Or call Juno at (800) 654-JUNO [654-5866]