Is the most malicious cookies do is put a keylogger on your browser?

I was wondering how far bad cookies go. I figured all they could do was put something that tracks you on your computer (keylogger), but I was wondering if they could also put something that actively searches what is already on your computer? Thanks in advance

A cookie is a text file. It cannot run, so it cannot actively search your computer for information. It can store information you enter into your web browser, but it cannot seek out and collect other information on your machine. As they are simple text files, you can open them and view the information stored in them.

A keylogger is a program that runs on your machine and records the keystrokes you make. A cookie is not a keylogger, and a keylogger is not a cookie.

A cookie only stores information that the website puts into it .

What happens with tracking cookies is that two different websites can use the one tracking cookie.

Cookies are fairly harmless, and often, even, quite helpful. Keyloggers, however, are very nasty, one of the worst sorts of infections you can have, and can steal your passwords and drain your bank account.

It requires very deep-level access to put a keylogger on a computer. Any malware that has sufficient access to put a keylogger on your computer also has enough access to cause your computer to do absolutely anything else it is capable of doing. However, you will not get anywhere close to this level of access using only cookies.

A malicious Flash-based ad on a website could do something like that however.

Sorry it has been a bit for my response. Good to know that cookies can’t do that. So at most they can only track websites, but not the typing you do on them?

Also, Flash-based ads can do something like that? That wasn’t even on my radar… would you be able to go into a little more detail about it?

Oh wait… is it that when the ad is going, since your computer is connected to the website the ad is on it can do something like track your typing?