[Samba] explorer.exe crashes on security tab access

[Jeremy Allison]

On Thu, Aug 16, 2018 at 07:35:46PM +0100, Rowland Penny via samba wrote:
> > 
> > The crash only happens when a local unix group (in this case root) is
> > set as the group for the shared file.
> 
> There is one very big problem with that theory, Administrator is
> mapped (in idmap.ldb) to root, so when you read 'root' on a DC, you
> can also read 'Administrator' (Which is most definitely a Domain
> user) ;-)

Whatever the case explorer.exe shouldn't crash on any data
returned from the server. If it does that's a possible
security flaw and you should report it immediately to
Microsoft (I just fixed a similar problem with libsmbclient
in our recent security release, that's why I'm sensitive
to these things).