Re: Use Cases and Requirements for Saving Files Securely

2009/11/12 Jonas Sicking <jonas@sicking.cc>

> 2009/11/12 Ian Fette (イアンフェッティ) <ifette@google.com>:
> > This is really getting into fantasy-land... Writing a file and hoping
> that
> > the user actually opens up explorer/finder/whatever and browses to some
> > folder deep within the profile directory, and then double clicks
> something?
> > Telling a user "click here and run blah to get a pony" is so much easier.
>
> So first off that only addresses one of the two attacks I listed.
>
>
Fair


> But even that case I don't think is that fantasy-y. The whole point of
> writing actual files is so that users can interact with the files,
> right? In doing so they'll be just a double-click away from running
> arbitrary malicious code. No warning dialogs or anything. Instead the
>

Why do you assume this? On Windows, we can write the MotW identifier, which
would lead to windows showing a warning. On linux, we could refuse to chmod
+x.


> attacker has a range of social engineering opportunities using file
> icon and name as to make doubleclicking the file inviting.
>
> Like I said, I think this might be possible to work around in the
> implementation by making sure to neuter all executable files before
> they go to disk.
>
> / Jonas
>