Rich - Thanks for chasing this study down. There is a lot of food for thought for all of us in it.

On 9/30/13 at 11:29 AM, [email protected] (Salz, Rich) wrote:

Bill said he wanted a piece of paper that could help verify his bank's certificate. I claimed he's in the extreme minority who would do that and he asked for proof.

I can only, vaguely, recall that one of the East Coast big banks (or perhaps the only one that is left) at one point had a third-party cert for their online banking and that it "encouraged" phishing of their customers. See also http://en.wikipedia.org/wiki/Phishing#cite_note-87

Found at: 
<http://www.nytimes.com/2007/02/05/technology/05secure.html?ex=1328331600&en=295ec5d0994b0755&ei=5090&partner=rssuserland&emc=rss>

To quote from the above:

    The idea is that if customers do not see their [preselected]
    image, they could be at a fraudulent Web site, dummied up to
    look like their bank’s, and should not enter their passwords.

    The Harvard and M.I.T. researchers tested that hypothesis. In
    October, they brought 67 Bank of America customers in the
    Boston area into a controlled environment and asked them to
    conduct routine online banking activities, like looking up
    account balances. But the researchers had secretly withdrawn
    the images.

    Of 60 participants who got that far into the study and whose
    results could be verified, 58 entered passwords anyway. Only
    two chose not to log on, citing security concerns.

This approach requires the customer to verify the image every log on. Conning them by replacing the image with, "Site undergoing maintenance"[1] is fairly easy. With my approach, I would authenticate the bank's key once, when I establish an account or sign up for online banking. My software would check that authentication every time I log on after that. (If the bank decides to change it's key every year, I might need a new piece of paper every year -- which might get old after a few years.)


and http://en.wikipedia.org/wiki/Phishing#cite_note-88 which say simple things like "show the right image" don't work.

Found at: 
<http://web.archive.org/web/20080406062154/http://people.seas.harvard.edu/~rachna/papers/emperor-security-indicators-bank-sitekey-phishing-study.pdf>

I believe this study is the one referred to in the NYT article above. This study started with 67 people, the same number mentioned above and the authors are also affiliated with Harvard and MIT. The steps they took to ethically use real accounts are worth reading.

The last test involved presenting a IE warning page, "There is a problem with this website's security certificate. The result was:

    Of the 60 participants whose responses to prior tasks had
    been verified, we were able to corroborate 57 participants’
    responses to the warning page. Despite the overtness of the
    warning page and its strong wording, 30 of 57 participants
    (53%) entered their passwords. 27 participants (47%) did
    not login.

Leaving me to say you shouldn't give the user an option to ignore security. I don't think I get a choice if an Apple or Microsoft software update fails signature verification.

Their conclusions:

    Users will enter their passwords even when HTTPS
    indicators are absent.

    Users will enter their passwords even if their site-
    authentication images are absent.

    Site-authentication images may cause users to disre-
    gard other important security indicators.

The last conclusion is interesting for evaluating other studies. They divided their subjects into three groups. Two used dummy accounts and one used their own accounts.

    Role playing has a significant negative effect on the
    security vigilance of study participants. Participants who
    played roles disregarded more attack clues before withholding
    their passwords than participants whose own passwords were at
    risk.

Cheers - Bill

[1] The text used in the second reference's study is very enticing:

    SAI Maintanance [sic] Notice:
    [bank name] is currently upgrading our award
    winning SAI feature. Please contact customer
    service if your SAI does not reappear within the
    next 24 hours.

-----------------------------------------------------------------------
Bill Frantz        | I like the farmers' market   | Periwinkle
(408)356-8506 | because I can get fruits and | 16345 Englewood Ave www.pwpconsult.com | vegetables without stickers. | Los Gatos, CA 95032

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