Re: Safe Browsing Mode - Revised

I quite like this idea, though there may be gotchas in how
it would/could be implemented (e.g. what if I have >1 browser
process running? I don't want to have to kill my linux distro
download just to check my bank balance). Still, to the extent
that it can be achieved, such a mostly-user-controlled safe
mode would be great.

Only biggish thing I'd add is maybe that there could be more
than one reasonable set of rules to apply in safe-mode. For
example, it could be that different rules would have to be
applied inside vs. outside a corporate network. Having
different rule-sets or whatever would also allow for future
developments, e.g. if at some point we become confident
enough in certificate status checking to make that a must
for safe-mode, then one could upgrade to start enforcing
that rule.

And a nit: this would of course become quite a target for
malware - controlling that list and associated rules would
be valuable.

S.

Bob Pinheiro wrote:
> *_Safe Browsing Mode: Definitions and Concept
> 
> _*Safe Browsing Mode is a special browsing window or tab that would 
> allow a particular user to visit only those websites that have been 
> previously determined to be trusted.  In most cases, each individual 
> user makes a determination of which websites are trusted.  In some 
> cases, users may rely on other trusted parties to determine which 
> websites are trusted.
> 
> Benefit of Safe Browsing Mode: User can be confident that any website 
> accessible via Safe Browsing Mode is trusted according to criteria 
> established by the user, or to criteria established by another party 
> that the user trusts.   
> 
> The means by which a user determines that a particular website is 
> trusted is not defined by Safe Browsing Mode. 
> 
>     * Determination that a website is trusted may depend on visual cues
>       associated with Extended Verification certificates, other cues,
>       user experience, or any other means the user chooses. 
> 
> Websites that have been determined to be trusted are placed on a White 
> List by the user (or other trusted party).
> 
>     * Via conscious user action?
>     * Via prompt from browser based on absence from existing White List?
>     * Other? 
> 
> A White List would consist of, at minimum, the URL of each trusted site, 
> and a “fingerprint” of the trusted site's certificate.
> 
>     * Fingerprint of a certificate is defined by OpenSSL as "the digest
>       of the DER encoded version of the whole certificate", where
>       "digest" is a hash function. 
> 
> Safe Browsing Mode would allow access only to those websites whose URLs 
> appear on the White List, and whose certificate fingerprints match the 
> fingerprint stored on the White List for each corresponding URL.
> 
> Safe Browsing Mode may be invoked in the following ways:
> 
>     * User would key in a secure attention sequence (such as
>       Ctl-Alt-Del) to invoke Safe Browsing Mode.  This would send a
>       signal to the OS that the OS should invoke Safe Browsing Mode in a
>       browser.
>     * User may choose a menu item in the browser to invoke Safe Browsing
>       Mode.
>     * Invoking Safe Browsing Mode via the OS may be more resistant to
>       attack than invoking it from within the browser itself.  
> 
> Third party validation services, such as OCSP certificate validation, 
> might be included in a browser's implementation of Safe Browsing Mode.
> 
> Safe Browsing Mode requires users to take specific actions to establish 
> trust in a website, add the website to the White List, and subsequently 
> invoke the Safe Browsing Mode tab or window.  Therefore, users may only 
> bother with Safe Browsing Mode for websites that require users to 
> provide sensitive personal information.
> 
> Industry groups such as the financial services industry could publish 
> White Lists of trusted sites.
> 
>     * Does browser need to query external White List?
>     * Do external White Lists get downloaded into User’s browser
>       whenever a change occurs? 
> 
>  
> *Safe Browsing Use Case 1:
> User Creates White List
> 
> *1.  User visits website in ordinary browsing mode and determines that 
> the website is trusted according to criteria set by the user; i.e., cues 
> triggered by EV certificates, other cues,
>      experience, etc.
> 
> 2.  Website URL and certificate signature are added to White List.
>  
> * 
> Safe Browsing Use Case 2:
> Viewing Trusted Websites in Safe Browsing Mode
> * 
> 1.   User invokes Safe Browsing Mode by keying in a secure attention 
> sequence.
> 
> 2.   Users provides a URL of website to be visited, or uses a bookmark. 
>         - Website will be viewable if URL is on White List and 
> certificate signature on White List matches certificate signature of 
> website.
>         - Bookmarks only show trusted sites on White List.
> 
> 3.  If URL is provided for a site not on the White List, user receives 
> some type of message indicating such.
>  
> * 
> Safe Browsing Use Case 3: 
> User Subscribes to White List Created by a Trusted  Industry Organization
> * 
> 1.  User subscribes to the “List of Official Banking Institutions That 
> Lend Money to Unemployed Philosphers”, published by the highly-regarded 
> Union of Unemployed Philosophers. 
>      The List contains URLs and certificate signatures of banking 
> website that have been verified as lending money to unemployed 
> philosophers. 
> 
> 2.  User receives a phishing email containing a link to a bank 
> advertising itself as providing loans to unemployed philosophers, and 
> offers very low interest rates on new loans.
> 
> 3.  User invokes Safe Browsing Mode by keying in secure attention 
> sequence. 
> 
> 4.  If User clicks on link in the email and a banking website opens in 
> Safe Browsing Mode, User is assured that the bank is legitimate and 
> provides loans to unemployed
>      philosophers. 
> 
> 5.  If the link in the email is bogus, a message appears when User 
> clicks the link, warning User that the link cannot be verified as 
> legitimate. 
>  
> 
>  
>

Received on Wednesday, 31 January 2007 09:17:27 UTC