Re: Reinventing the wheel (aka "Decoding Netscape Mail passwords")

[aleph1 () UNDERGROUND ORG (Aleph One)]

On Thu, Dec 16, 1999 at 01:33:10PM -0500, Tim Hollebeek wrote:
> In addition, the consequences of this flaw in a Windows environment are
> substantially different, due to the lack of access controls.  As we
> discussed in the technical summary, while there is no perfect solution to
> this problem, it would take very little work for Netscape to make future
> exploits of this type much more difficult.  The current position of
> Netscape, that these sorts of vulnerabilities need not be fixed, is in my
> opinion rather irresponsible.  Software companies have a responsibility to
> make exploiting their software as difficult as possible, _especially_ in
> cases like this where the cost to do so is similar to, or less than, the
> cost of using absurdly weak proprietary cryptography.  It is Netscape's
> responsibility to put the bar at as high a level as is feasible and
> economical.  As Avi Rubin, security expert at ATT Labs, pointed out, in this
> case Netscape needs to run out and get a bar so they can raise it.

This is a red herring. Local secure storage of secrets in PCs without another
secret is not possible. We've had this discussion before on the list in
reference with many client applications (including Netscape). If you are
using a known key a better encryption algorithm is useless. Regardless
of the algorithm its nothing more than obfuscation.

For encryption to be of any use you need to encrypt the information
you want to maintain secret with yet another secret, but the user does
not want to be bothered with remembering another password. That is the reason
they ask the client application to remember their password in the first place.

Local secure storage of secrets is a service that needs to be provided
by the operating system. In the case of Windows NT you can store them
(with some limitations) using the Local System Authority (LSA) API. Under
Windows 95/98 there is an API to store secrets using the users logon password
(stores the secrets in .PWL files) but to my knowledge it is not documented
by Microsoft (although they allude to it in some early Windows 95 presentation
slides). Maybe someone with more knowledge of Microsoft operating systems
can confirm?

So given these constrains the best thing Netscape can do is not use any
obfuscation at all and store the passwords in plain text. At least this
does not give the user any false sense of security.

On a side note, I am surprised this made it into CNN. A dozen more
serious vulnerabilities have been found in Netscape and Internet Explorer
and they don't even notice, yet they pick up on this rather minor issue.
Go figure.

> Tim Hollebeek
> Reliable Software Technologies

--
Aleph One / aleph1 () underground org
http://underground.org/
KeyID 1024/948FD6B5
Fingerprint EE C9 E8 AA CB AF 09 61  8C 39 EA 47 A8 6A B8 01