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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 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

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, as long as it was changed from [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), in the request shows that it is 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. Here, for example, is a table of types of several of the most frequently used types of data:

Data description File extension MIME type
Pictures gif 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 /
MS Power Point ppt application /
Adobe Acrobat file pdf application / pdf
Flash document swf application / x-shockwave-flash