JS and proxies.

[Billy]

Does anyone know how often JS is used to grab someone's IP address even
if they are using a proxy?

For example if they are using a proxy with webmail such as Yahoo,
Hotmail or Lycos.

Or is this just an example of paranoia!?

 

[Christopher J. Hahn]

Does anyone know how often JS is used to grab someone's IP address even
if they are using a proxy?

For example if they are using a proxy with webmail such as Yahoo,
Hotmail or Lycos.

Or is this just an example of paranoia!?

So far as I know, JavaScript has no way of accessing the IP address of
the client machine, regardless of proxies.

I believe VBScript can, though. You might want to inquire in a VBScript
group about that one, because it's effectually little different. If
it's possible, a simple protection is... use something other than
Internet Explorer.

 

[Randy Webb]

Can't do with js, no access to it per se, is usually done on the
server end, quite easy on the server, there's a global variable you can
use to get it, $REMOTE_ADDR.

And that variable is totally useless when trying to get my IP address.

 

[Christopher J. Hahn]

Can't do with js, no access to it per se, is usually done on the server
end, quite easy on the server, there's a global variable you can use to
get it, $REMOTE_ADDR.

Danny

That would be sufficient for anybody not using a proxy, yes. But the OP
is worried about whether there's a client-side way to obtain his local
IP even when he is behind a proxy.

The REMOTE_ADDR, in this case, would be the IP address of the proxy
server. Use of proxies is common to try to hide one's IP from a remote
machine, either for privacy or traceability reasons.

 

[VK]

Does anyone know how often JS is used to grab someone's IP address even

if they are using a proxy?

Not with JavaScript (all browsers exept IE).

Possible with JScript (IE 5.0 and higher) using it as a transport to
VBScript over
execScript().
*But* only if user is stupid enough to click Yes on "this page contains
potentially dangerous content".
If you move security settings to High, when nothing to worry about at
all (popup will not appear, script not executed). Lesser users take
security decisions - better for company