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Vulnerability NAV Affected NAV Description Chris Foster found following. While testing escalation of privileges from a normal user to admin he found that in his NTS 4.0/SP6 installation with Norton Antivirus 5.02 installed this is very simple. Here are the details on how this is done: 1. Logon as a normal user. Try to run windisk from the run prompt and you should get an access denied. 2. Browse to the root directory for the NAV installation and rename navlu32.exe to navlu32.old. Create navlu32.exe that executes the command: net localgroup administrators {name of account to escalate} /ADD 3. Open the Norton Program Scheduler by executing nschednt.exe in the installation directory. Since normal users are restricted as to what they can run. (Display Message, Scan for Viruses, Run LiveUpdate) Just schedule a LiveUpdate for a couple of mins ahead. When your scheduled job runs it will execute your navlu32.exe. Log back on and you now have admin privs and can execute windisk or whatever you like for that matter. This works due to the Norton Program Scheduler running with system privs and a normal user being able to write to the Norton installation directory. Exactly the same problem exists with netshield 4.0.3 and VirusscanNT 4.0.3 from Networkassociates (tested on NT4 SP5). Just replace scan32.exe with e.g. cmd.exe schedule a scan some minutes in the future and you'll get a shell running with more privileges you had. Solution Hmm... Interesting, but needs an idiot admin to exploit. This requires you have write access to the NAV installation. Only a very stupid admin would allow that to happen. The program scheduler has a good argument for needing system privs (like, updating system file, such as the NAV installation). Solutions? 1) Don't let users have write access to /Program Files (or the NAV installation, wherever it is) 2) Install trusted binaries in a different location (/WINNT isn't an option, if you want certification from MS).