Message-ID: <73540947.1514831286507443185.JavaMail.root@plumbob.merit.edu>
Date: Thu, 7 Oct 2010 23:10:43 -0400 (EDT)
From: Ryan Sears <rdsears@....edu>
To: full-disclosure <full-disclosure@...ts.grok.org.uk>
Subject: Filezilla's silent caching of user's credentials

Hi all,

As some of you may or may not be aware, the popular (and IMHO one of the best) FTP/SCP program Filezilla caches your credentials for every host you connect to, without either warning or ability to change this without editing an XML file. There have been quite a few bug and features requests filed, and they all get closed or rejected within a week or so. I also posted something in the developer forum inquiring about this, and received this response:

"I do not see any harm in storing credentials as long as the rest of your system is properly secure as it should be."

Source:(http://forum.filezilla-project.org/viewtopic.php?f=3&t=17932)

To me this is not only concerning, but also completely un-acceptable. The passwords all get stored in PLAIN TEXT within your %appdata% directory in an XML file. This is particularly dangerous in multi-user environments with local profiles, because as we all know physical access to a computer means it's elementary at best to acquire information off it. Permissions only work if your operating system chooses to respect them, not to mention how simple it is *even today* to maliciously get around windows networks using pass-the-hash along with network token manipulation techniques.

There has even been a bug filed that draws out great ways to psudo-mitigate this using built-in windows API calls, but it doesn't seem to really be going anywhere. This really concerns me because a number of my coworkers and friends were un-aware of this behavior, and I didn't even know about it until I'd been using it for a year or so. All I really want to see is at the very least just some warning that Filezilla does this. 

Filezilla bug report:(http://trac.filezilla-project.org/ticket/5530)

My feelings have been said a lot more eloquently than I could ever hope to in that bug report:

"Whoever keeps closing this issue and/or dismissing its importance understands neither security nor logical argument. I apologize for the slam, but it is undeniably true. Making the same mistake over and over does not make it any less of a mistake. The fact that a critical deficiency has existed for years does not make it any less critical a deficiency. Similarly, the fact that there are others (pidgin) who indulge in the same faulty reasoning does not make the reasoning any more sound." ~btrower

While it's true you can mitigate this behavior, why should it even be enabled by default? The total lapse in security for such a feature-rich, robust piece of software is quite disturbing, and I don't understand how the developers don't think this is an issue. 

I just wanted to gauge the FD community on this issue, because with enough backing and explanation from the security community as to why this is a problem, this issue may finally be resolved (it's been doing this for years now). 

Regards,
Ryan Sears

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