Website Refuses Ad-Blocked Browsers

Everything about using Adblock Plus on Mozilla Firefox, Thunderbird and SeaMonkey

Website Refuses Ad-Blocked Browsers

Postby Kraig » Wed May 21, 2008 11:44 pm

I have not ever known a site refuse an ad-blocked browser before, this is new on me!!

see for yourself!! after a few seconds, you get what is in the screenshot.

http://sepecat.info/b/

here is the screen shot:

Image

and the link to his hmepage is

http://sepecat.info/ , which strangely links back to the first link in this post, and you get the same thing again :?
Kraig
 
Posts: 1
Joined: Wed May 21, 2008 11:34 pm

Postby Ares2 » Thu May 22, 2008 12:04 am

You can use this whitelist while browsing on the site:
Code: Select all
@@http://pagead2.googlesyndication.com/pagead/show_ads.js
Ares2
 
Posts: 1275
Joined: Fri Feb 15, 2008 1:47 pm

Postby Wladimir Palant » Thu May 22, 2008 1:09 am

This site doesn't really detect Adblock Plus, it can only see that Google ads didn't load. Funny enough, you can just click "Back" on the error page and you will be able to read the page just fine. Generally, these things can only be really "fixed" with a GreaseMonkey script.
Wladimir Palant
ABP Developer
 
Posts: 8395
Joined: Fri Jun 09, 2006 6:59 pm
Location: Cologne, Germany

Postby rick752 » Thu May 22, 2008 1:40 am

Wow .. look .. it's the old 'unbeatable' Danny Carlton anti-adblocking code :D. The failure of that code caused a very angry Danny Carlton to instead block ALL Firefox users. What an internet news story THAT was last summer :shock:

I removed the fix from the EasyList after Danny gave up because I didn't think that anyone would ever try to use that script again. Guess I was wrong.

Unless that script tries to make a comeback, I will leave things as they are.
Last edited by rick752 on Thu May 22, 2008 5:36 am, edited 1 time in total.
User avatar
rick752
 
Posts: 2709
Joined: Fri Jun 09, 2006 7:59 pm
Location: New York USA

Postby Ares2 » Thu May 22, 2008 3:16 am

Wladimir Palant wrote:these things can only be really "fixed" with a GreaseMonkey script.


Can you give me an example script? Can a script block another one or can it just remove the redirecting or hiding? (I guess I should really learn JS :roll: )
Ares2
 
Posts: 1275
Joined: Fri Feb 15, 2008 1:47 pm

Postby Wladimir Palant » Thu May 22, 2008 8:38 am

@Ares2: Something like that should do:

Code: Select all
// ==UserScript==
// @name          sepecat.info Anti-Anti-Adblocker
// @namespace     http://adblockplus.org/forum/viewtopic.php?t=2441
// @description   Disables the anti-adblocking script on sepecat.info
// @include       http://sepecat.info/*
// ==/UserScript==

window.addEventListener("load", function() {
  unsafeWindow.reklama = function(){}
}, false);
Last edited by Wladimir Palant on Thu May 22, 2008 4:05 pm, edited 1 time in total.
Wladimir Palant
ABP Developer
 
Posts: 8395
Joined: Fri Jun 09, 2006 6:59 pm
Location: Cologne, Germany

Postby Dr. Evil » Thu May 22, 2008 4:01 pm

I think it should look more like this:
Code: Select all
// ==UserScript==
// @name          sepecat.info Anti-Anti-Adblocker
// @namespace     http://adblockplus.org/forum/viewtopic.php?t=2441
// @description   Disables the anti-adblocking script on sepecat.info
// @include       http://sepecat.info/*
// ==/UserScript==

location.href = "javascript:window.reklama = function(){}";


when just setting unsafeWindow.reklama, the site could use a property setter to access the GM_* functions.
Dr. Evil
 
Posts: 194
Joined: Fri Sep 08, 2006 3:51 pm

Postby Wladimir Palant » Thu May 22, 2008 4:07 pm

@Dr.Evil: Right, it should be unsafeWindow - I corrected the code above. As to property setters - I don't think the site can use them to access anything, this vulnerability was closed long ago. Changing window's location on the other hand has undesirable side-effects.
Wladimir Palant
ABP Developer
 
Posts: 8395
Joined: Fri Jun 09, 2006 6:59 pm
Location: Cologne, Germany

Postby Dr. Evil » Thu May 22, 2008 4:28 pm

the official greasemonkey wiki says that unsafeWindow *is* unsafe and recommends using location.href: http://wiki.greasespot.net/UnsafeWindow

As far as I know, setting location.href to a javascript uri doesn't have any side effects... it just executes the script, like a javascript: link or a bookmarklet.

There's also a lengthy read on that topic here:
http://www.oreillynet.com/pub/a/network ... falls.html

Maybe XPCSafeJSObjectWrappers are a solution for this problem, but only in Firefox 3.
Dr. Evil
 
Posts: 194
Joined: Fri Sep 08, 2006 3:51 pm

Postby Wladimir Palant » Thu May 22, 2008 4:38 pm

Setting window location to a JavaScript URL aborts all loading that is still in progress, stops animated GIFs and probably also clears all timeouts set by JavaScript. So the side-effects are rather numerous. But if one doesn't care, using this approach should indeed be safer, at least with respect to potential not yet discovered security holes in the browser.
Wladimir Palant
ABP Developer
 
Posts: 8395
Joined: Fri Jun 09, 2006 6:59 pm
Location: Cologne, Germany

Postby Ares2 » Thu May 22, 2008 5:33 pm

Wladimir Palant wrote:@Ares2: Something like that should do:

Cool, thank you very much, this works (Next step for me is to understand HOW it works :D ).

@Dr. Evil: I just get this when I use your script for this site:
Image
Any ideas what's wrong?
Ares2
 
Posts: 1275
Joined: Fri Feb 15, 2008 1:47 pm

Postby Wladimir Palant » Thu May 22, 2008 5:35 pm

@Ares2: Should be:
Code: Select all
location.href = "javascript:void(window.reklama = function(){})";
Wladimir Palant
ABP Developer
 
Posts: 8395
Joined: Fri Jun 09, 2006 6:59 pm
Location: Cologne, Germany

Postby Ares2 » Thu May 22, 2008 5:59 pm

Wladimir Palant wrote:@Ares2: Should be:
Code: Select all
location.href = "javascript:void(window.reklama = function(){})";

Yes, now it works.

Correct me if I'm wrong but these scripts work for every function x using window.location = "url" ?
Ares2
 
Posts: 1275
Joined: Fri Feb 15, 2008 1:47 pm


Return to Adblock Plus for Firefox support

Who is online

Users browsing this forum: Andreascrt, Antoniotpm, KemppiOr, Ruslanotz and 14 guests