We do copy various data by ‘ctrl+c’ for pasting elsewhere. This copied data is stored in clipboard and is accessible from the net by a combination of JavaScript’s and ASP.
Just try this:
1) Copy any text by ‘ctrl+c’
2) Click the Link:
3) You will see the text you copied on the Screen which was accessed by this web page.
Do not keep sensitive data (like Passwords, Credit card numbers, PIN, etc.) in the clipboard while surfing the web. It is extremely easy to extract the text stored in the clipboard to steal your sensitive information.

Remady :
We can get secured by..
Go to *Control Panel->Internet Options->Security->Internet->Custom Level*
Navigate to *Scripting*
In this, *Disable* the option *Allow paste operations via script*.
This disables the reading of the clipboard.

But as mentioned, be careful to keep the confidential data secured while surfing.