Re: Mozilla Thunderbird SMTP down-negotiation weakness

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

> I have to agree. Lets not forget that STILL all Mozilla products fail to 
> show RSA/asymmetric keysize in any sensible format. Users of Mozilla 
> products have no idea about safety of SSL/TLS connections, since the 
> information about asymmetric keysize is not shown properly (= read: Its 
> not shown at all unless you want to start calculating it from the raw 
> form of the asymmetric key).
>
> You can easily check the symmetric (RC4/AES) keysize (40/56/64/128/256 
> bits) when selecting "Page info" - "Security", but nothing shows you how 
> large the asymmetric keysize is (512/1024/2048/4096 bits)! This is very, 
> very stupid.
>
> Firefox, for example tells you that you have "high grade encryption" 
> when you have AES-256-CBC with 512bit RSA! Since 512bit RSA only gives a 
> work factor of about 2^60 and AES-256-CBC about 2^120 (if you think the 
> most advanced attacks that only work in very, very theoretical form 
> could be implemented against it)...well, who would even dream on 
> cracking AES-256 when all they have to do is to crack 512bit RSA to get 
> even better solution!

I agree that this is less than optimal.  Could you point me to the bug
report you filed in bugzilla that requests these changes?


> It cant be THAT HARD to implement a feature onto Mozilla products that 
> would show asymmetric keysize. Opera does it. IE does it. Why cant the 
> geeks at Mozilla do it too? Because the seem to lack even basic 
> knowledge of crypto...   :(

It probably isn't that hard.  Why don't you write a patch?  Welcome to
open source.  You can easily make a community contribution and make the
world better for every Mozilla user.  Probably even get your name in the
credits!


Honestly though, this stuff is such a miniscule portion of overall
security...  How many users actually care when websites don't even have
valid certificates?  Heck, most browsers don't even check for CRLs by
default, including IE.

There are many many more, much easier ways to steal someone's sensitive
info without attacking the crypto.

tim
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