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SECURITY: UNIX Netscape 3.x - 4.5 MIME type overflow problem.



----- Forwarded message from Bob Tanner <tanner@real-time.com> -----
> > UNIX users should take the action described, please note this is in all
> > versions of Netscape since 3.0, version 2.x and before did not have the
> > feature that causes the problem.
> > 
> > http://home.netscape.com/products/security/resources/bugs/mimebufferoverflow.html
> > 
> > The MIME Type Buffer Overflow Vulnerability 
> > October 22, 1998 
> > 
> > Netscape has recently been alerted to a security vulnerability that
> > affects the Netscape Navigator browser software. The MIME Type Buffer
> > Overflow vulnerability affects the Unix versions of Navigator 3.0x and
> > 4.0x and Netscape Communicator 4.5. (Note: Windows and Mac OS versions are
> > NOT affected.) Although Netscape has verified this bug, no customer
> > incidents of lost or stolen data have been reported to Netscape. Netscape
> > takes all potential security and privacy issues seriously and is currently
> > working on a fix. An update will be posted on the Netscape web site soon.
> > 
> > Under ordinary circumstances, users browsing known, trusted sites are not
> > at risk.  When a user visits a web site that requires a plug-in that is
> > not currently installed, the Null Plug-in dialog box appears to assist the
> > user in locating the correct plug-in.  However, if the user visits an
> > unknown or untrusted site, a hacker operating through that site could
> > exploit a weakness in the Null Plug-in mechanism to force Navigator or
> > Communicator to crash. In theory, this vulnerability could enable a hacker
> > to execute an untrusted program on the user's machine. No instances of
> > this nature have been reported to Netscape, however.
> > 
> > You can avoid this vulnerability by setting a preference for Navigator to
> > prompt you before it attempts to download a plug-in with an unknown MIME
> > type. To do this, follow these steps:
> > 
> > 	1.	In Communicator, select Preferences from the Edit menu. 
> > 	2.	In the Preferences dialog box, select the Navigator category. 
> > 	3.	Select Applications. 
> > 	4.	On the Description list, select the * entry (handled by
> > 		Plug-in: Netscape Default).
> > 	5.	Click the Edit button. 
> > 	6.	Set Handled By to Unknown: PromptUser. 
> > 	7.	Click OK to close the Edit Type dialog box. 
> > 	8.	Click OK to closed the Preferences dialog box. 
> > 	9.	Quite Navigator or Communicator and restart the program. 
> > 
> > Setting this prompt will not impair your ability to view pages with other
> > plug-ins you already have installed, and you will retain the ability to
> > manually download and install new plug-ins as you need them.
> > 
> > --- Note from Dan:
> > 
> > It is always good to know that software you use may have security holes.
> > Usually a quick search of the web or security/bug sites such as bugtraq or
> > l0pht or even the products own page will enlighten you.
> > 
> > This security advisory was found by doing an altavista search on "netscape
> > security".  Many software houses have a security page on their web site.
> > It is not always easy to find.
> 

----- End forwarded message -----

-- 
Bob Tanner <tanner@real-time.com>       | Phone : (612)943-8700
http://www.real-time.com                | Fax   : (612)943-8500
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