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What your browser says

While visiting websites, downloading files, your browser sends so-called HTTP requests (requests), informing which page you need, each such request contains different information necessary for connecting the browser and website: Your operating system type systems (Windows 98/2000 / XP, etc.) and the type of browser used, this data can be used to detect vulnerabilities

Additional information gathered by java-script you:



This example shows a request for the file progs.shtmll in the anti directory on the server 127.0.0.23.


Environment variables that may be in the request (the request may be changed by the proxy server)

"Accept-Language" - Informs the remote computer about the language used by your browser. This information can be used to restrict access to resources or for other purposes.

"Referrer" - allows you to identify your interests :) i.e. where did you come from this resource

"Cookies" - They can contain a huge amount of information, such as e-mail, address, passwords ... All this information is in the headers of HTTP requests.

"Accept-Encoding:" - Informs the remote computer about the encoding accepted by your browser.

"If-Modified-Since:" - Download the file if it has been changed since [date / time]

"(proxy) _connection" - Connection type. "Close" and "Keep-Alive" are the two main types of connection. The first is typical for proxy servers, the second is used by browsers for direct connection. Some proxy servers support "Keep-Alive", it looks like a direct connection of the browser. The presence of information Proxy_ (Connection), the request shows that it was made through a proxy server. But some websites do not connect without this information. In addition, some proxies themselves change the data in accordance with their settings

"User-Agent:" - Contains information about your OS and browser type.

"Host:" - The requested host.

"Accept:" - Informs the remote computer about the type of information you are accessing. Each data type corresponds to the so-called MIME type. This type is described by a character set reflecting the type of data used. For example, here is a table of the types of several of the most frequently used types of data:

Data description File extension MIME type
Gif pictures gif image / gif
Jpeg pictures jpeg jpg jpe image / jpeg
VRML files wrl vrml model / vrml
Html document html htm text / html
Plain text asc txt text / plain
ZIP archive zip application / zip
MS Word file doc application / msword
MS Excel file xls application / vnd.ms-excel
MS Power Point ppt application / vnd.ms-powerpoint
Adobe Acrobat file pdf application / pdf
Flash document swf application / x-shockwave-flash