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Hi ClearClick! Good bye Clickjacking?


Javascript is not necessarily needed to execute Clickjacking.JavaScript might make the attacker’s life easier, but it’s not inevitable to make the attack. Alternatively the attacker can use frame tags to load any site of their choice in the background and using another div tag redirect the user to any other site of choice. No role of Javascript here. Mitigation? Don't load frame in your browser in any case. all it takes is including this piece of javascript in your page:


This works in most browsers, with Internet Explorer being a notable exception.
IE8 comes with another new technique.The fix is actually very simple: it lets website owners include an extra tag in their pages that tells Internet Explorer the page is not supposed to be included in a frame. It’s called X-FRAME-OPTIONS;
a value of DENY means the page should never be opened in a frame, and
SAMEORIGIN only allows it to be framed within pages from the same site.
Any other use will show a warning, and a link that opens the page in a
new screen.
There are efforts to make Firefox too compatible to it .

But for the time being, Firefox users can use the a plug in ClearClick by NoScript.
Default protections that NoScript has provided for a long time, i.e. JavaScript and plugin blocking can prevent most clickjacking attacks. In older version, though, to be 100% protected against Clickjacking you needed to enable the Forbid IFRAME and possibly Apply these restrictions to trusted sites as well NoScript options.
Fortunately, since version 1.8.2, NoScript provides a new default kind of protection called ClearClick, which defeats clickjacking no matter if you block frames or not . Even better, ClearClick can protect you from Clickjacking / UI-redressing attack independently from JavaScript and plugins blocking: you can even Allow scripts globally (which is not recommended anyway), and your ClearClick still works.

Clickjacking hides or displaces or partially covers something you wouldn't want to click, if you could see it in its original context. ClearClick does the opposite: whenever you click a plugin object or a framed page, it takes a screenshot of it alone and opaque (i.e. an image of it with no transparencies and no overlaying objects), then compares it with a screenshot of the parent page as you can see it. If the two images differ, a clickjacking attack is probably happening and NoScript raises a "ClearClick warning",

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