[svlug] (forw) Re: Heartbleed

[Rick Moen]

Quoting "Karsten M. Self" (karsten at linuxmafia.com):

> You didn't mention the (possibly considered self-evident) point that
> **EVERY PASSWORD YOU USE ON EVERY SITE SHOULD BE UNIQUE**.  I'd
> highlight that as the mouth-breathers will fail to grasp the point.  

Word.

I just wrote about this for SF-LUG, so I'll be lazy and quote.

 'To summarise the summary of the summary, people are a problem.' --
 Douglas Adams, _The Restaurant at the End of the Universe_.  In
 particular, humans' wetware is poorly engineered to remember complex
 passwords well, especially many of them at once.  Bioengineering being
 insufficiently far advanced, we aspire to lean on our silicon friends.

 Forgetting passwords causes loss and downtime.  That is a threat model
 of sorts (DoSing yourself).

 Using ridiculously simple passwords (so you can remember them)
 facilitates dictionary attacks, a second threat model.

 Using the same moderately complex passwords in multiple scenarios
 (because you can only remember a few) creates the risk that compromise
 of credentials in one place will let intruders trivially masquerade as
 you in other places they have figured out you likely use, a third threat
 model.

 Using a bunch of complex passwords that you write on PostIts addresses
 pretty much all of those threats, while creating a limited exposure to
 the threat of someone visiting your desk and writing them down, a fourth
 threat model.  (Don't laugh at the PostIt person, though.  His or her
 desk may be pretty difficult to break into, and, if he/she doesn't write
 unambiguously on each PostIt what it's the password _for_, that may not
 be much of a risk.)

 So, some clever person thinks:  'I know!  I'll write a "password safe"
 application that runs on my {workstation|smartphone}.'  So, the user
 need remember only _one_ complex password, the one that unlocks all the
 others.  Great, eh?

 Anyone spot the problem?  Anyone?  Anyone?  Bueller?

 Hint:  Has an workstation or smartphone ever suffered a security
 problem?




> My own practice for over a decade has been to use pwgen, a utility
> available on Debian, to create long passwords.  I'm usually shooting
> for between 20-40 characters as a default, though I'll generate
> shorter ones if sites don't allow longer.  pwgen also allows for
> passwords matching various character inclusion/exclusion rules to be
> created if necessary (those rules generally _weaken_ password
> security, but that's a whole 'nother rant).

The famous xkcd method is still popular.  http://xkcd.com/936/
Turns out, Schneier has pointed out that this is no longer very good:
https://www.schneier.com/blog/archives/2014/03/choosing_secure_1.html
He makes an alternative suggestion, the 'Schneir scheme' he outlined 
in 2008:

   So if you want your password to be hard to guess, you should choose
   something that this process will miss. My advice is to take a sentence
   and turn it into a password. Something like "This little piggy went to
   market" might become "tlpWENT2m". That nine-character password won't be
   in anyone's dictionary. Of course, don't use this one, because I've
   written about it. Choose your own sentence -- something personal.

I have a heuristic of my own.  And no, I won't say what it is.  ;->


> I store my passwords in an ASCII text file encrypted via PGP.  There are
> other alternatives, including multiple password managers, various of
> which have their own failings. 

Yes, including the SPoF problem that I wanted to escalate to Ferris
Bueller, above.


> I'm not sure that gutting large segments of SSL/TLS and the CA
> infrastructure might save us, or at least doom us in new and novel ways,
> but suggestions here too might be useful.

I'm up for gutting the whole Certificate Authority system as an
excellent start.  (Monkeysphere, anyone?)


Quoting another bit from my SF-LUG post:

 > yes, rick, i'd love to hear your point of view.

 My personal electronics includes a laughably antique Palm TX PDA.  Yes,
 a PDA!  In 2014!

 Gosh, what's wrong with a PDA?  Well, it's detached from the Internet.
 Because I'm utterly paranoid about what I am and am not willing to
 install on it, it has only extremely simple, well-known software.

 In security terms, the term for that first wrong thing is 'airgapped'.
 In security terms, the term for that second wrong thing is 'very small
 and very hard attack surface.'

 My calling those somethings 'wrong' with my PDA is 98% sarcasm:  In the
 security context, both are highly advantageous.

 My PDA's very small collection of software includes an open-source
 PalmOS application called Keyring.  http://gnukeyring.sourceforge.net/
 Keyring is an _offline_ store for security data including but not
 limited to passwords.

 I back up its 3DES-encrypted datastore to my workstation.  I'd be glad
 to give you a copy of my key database.  In security terms, that is
 called 'making backups'.  ;->

 No, I cannot copy/paste passwords onto my workstation.  Yes, that means
 I must type them.  Yes, I do make sure people are not shoulder-surfing
 my Palm TX's screen when I have Keyring open.  Yes, Keyring does timeout
 any open display.

 If I give up on PalmOS devices, yes, I'll have to find something else --
 but I'm reluctant to have that be anything on a workstation or
 smartphone, because of that thing you're going to detail in your
 homework assignment.

 Disclaimer:  Your Mileage May Differ.[tm]  And people's degree of
 paranoia needs to be crafted to suit their indvidual needs.