Wow. Lotsa data. Thanks a bunch...
> The browser keeps track of what the applets are doing. Under
> some conditions it modifies the capabilities available to an
> applet after certain events. For example, the network class
> loader keeps track of whether or not the applet came from
> "within" the firewall (direct access to host) or "outside"
> the firewall (through the firewall). It also keeps track
> of any files or sockets the applet opens. If the applet
> opens any socket or file that is bound "inside" the firewall
> (any file, and host inside the firewall) it is prevented
> from ever opening a connection to a host "outside" the
This bothers me. Having the browser able to open a socket at all rings
up a big red flag saying "DANGER" with a tinny siren and stuff. For example,
it could look for well known proxies within the firewall (CERN HTTPD, for
example), look for a nameserver and get a copy of the local domain and
try rshing to all the hosts, and so on. Once it's got a socket open to
some place it can pump data through it's got you... it can then stage an
attack from the compromised system.
I'd really like to get some feedback on how this is prevented, especially
given the following comment...
> OK, after having someone send me a "finger" applet in Java,
> I'll have to say that it is in no way a "secure" language in
> the sense that MUF, MPI, Secure Tcl, or even Postscript is.
> This is disappointing... hopefully Sun will realise they need
> another string for this bow. Perhaps that's why they're
> supporting Tcl development as all.
> Writing finger in Java is trivial, getting it to execute as an applet is
> "hard". The browser knows where you're applet came from and where its
> linking too, an external (outside the firewall) trying to do a finger
> inside the firewall is allowed,
This implies that an applet can open sockets to sites within the firewall.
So, it can run the equivalent of Satan or ISS and if it finds a hole it can
use it to open a channel to the outside world. All the time running a really
cool animation so the victim doesn't worry about why it's taking so long.
Maybe a Christmas Tree?
I would be much happier if the Java browser was shipped as default with
permissions such that network connections and file access from applets
was completely verboten, and tell people how they can turn them back on.
> :: Let's say your a manufacturer of novelties and you decide
> :: to sell a paper weight which consists of a small caliber
> :: pistol and six rounds of ammunition encased in thick Lexan(tm)
> :: resin. And you sell these to kids. It doesn't matter that
> :: there is no known or postulated way for getting the gun
> :: out of the resin in working order, and that there are other
> :: ways for kids to acutally buy working guns, you will be
> :: labelled by the press as selling guns to kids.
Just make sure your resin isn't soluble in acetone.
Peter da Silva `-_-'
Network Management Technology Incorporated 'U`
1601 Industrial Blvd. Sugar Land, TX 77478 USA
+1 713 274 5180 "Har du kramat din varg idag?"