Same ol' massive MITM exposure in Netscape 2.01b

Just to repeat old news: Netscape 2 has similar  exposure to MITM attacks 
to 1.1. 

Netscape 2 does make one variant of the MITM attack less useful: The 
new document  info page allows information to be obtained about inlined 
images as well as the base page; this breaks the old attack of only 
intercepting inline image requests (which can be used to steal 
information in request headers without there being any chance of your 
certificate showing up). 


1) The client does not do any verification that the certificate used for 
the transaction is one associated with the server, allowing MITM 
substitutions as long as the server has a properly signed certificate

2) The client does not issue warnings for redirections from one https 
page to another https page, even if the url to which it is redirected has 
a different hostname to the url originally dereferenced.

3) In the case of redirection, the document info screen does not provide 
information about the originaly referenced page, just the final page. 
This allows the MITM to intercept the first request, steal the request 
data, then issue a redirect to hide the certificate used in the intercept. 

4) In the beta version, the document info page does not display the 
security info (I did check with  MITM disabled). 


Simon

-----
(defun modexpt (x y n)  "computes (x^y) mod n"
  (cond ((= y 0) 1) 	((= y 1) (mod x n))
	((evenp y) (mod (expt (modexpt x (/ y 2) n) 2) n))
	(t (mod (* x (modexpt x (1- y) n)) n))))

Simon Spero wrote:
> 1) The client does not do any verification that the certificate used for
> the transaction is one associated with the server, allowing MITM
> substitutions as long as the server has a properly signed certificate
> 
> 2) The client does not issue warnings for redirections from one https
> page to another https page, even if the url to which it is redirected has
> a different hostname to the url originally dereferenced.

  I'm working on these right now.  A future beta will have fixes for
this.

> 3) In the case of redirection, the document info screen does not provide
> information about the originaly referenced page, just the final page.
> This allows the MITM to intercept the first request, steal the request
> data, then issue a redirect to hide the certificate used in the intercept.

  If the previous two are fixed, it doesn't seem that this is really
important.

> 4) In the beta version, the document info page does not display the
> security info (I did check with  MITM disabled).

  Did you have the disk cache turned off?

	--Jeff

-- 
Jeff Weinstein - Electronic Munitions Specialist
Netscape Communication Corporation
jsw@netscape.com - http://home.netscape.com/people/jsw
Any opinions expressed above are mine.