Re: Evilgrade 2.0 - the update explotation framework is back

[Tim <tim-security () sentinelchicken org>]

Valdis,

I've read all of your postings on this thread and I just don't buy
what you're saying.


> Except if a signing key gets compromised, as happened to one Linux vendor
> recently, causing a lot of kerfluffle...  Setting up a proper signing system
> involves a certain amount of actual cost and effort.  And every organization
> that produces code, be it for-profit proprietary code or free open-source code,
> has to make resource tradeoffs.

Having a signing key that is poorly protected at the vendor's offices
is still better than not signing any updates.


> Is there any actual *evidence* that hijacking "authorized" updates is a big
> enough problem to be worth it?  If each year, 5 of their customers get pwned
> by the sort of attack that Evilgrade does, but 50,000 get pwned by "click here"
> popups that code signing won't do squat to prevent, is it really worth their
> time and effort?  Sure, sucks to be one of the 5, but if they instead spend the
> resources to do something *else* to make their customer's lives better that would
> benefit thousands rather than the 5....

It *really* doesn't take that much effort to enforce SSL/TLS
certificate verification in the automated update process.  You don't
need to do anything special with "code signing".  Just check for
updates via HTTPS URLs and require that verification checks out.

tim

_______________________________________________
Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/