Malwarebytes intentionally does not search for and remove cookies because they pose no significant threat...it has more important things to look for.
We do not detect or remove cookies as they are not considered a malware threat to your system. There are plenty of 3rd party programs to remove or you can even have most browsers automatically remove if you like.
Malwarebytes forum, Post #2 by AdvancedSetup (Root Admin)
Cookies are text string messages given to a Web browser by a Web server. Whenever you visit a web page or navigate different pages with your browser, the web site generates a unique ID number which your browser stores in a text (cookie) file that is sent back to the server each time the browser requests a page from that server. Cookies allow third-party providers such as ad serving networks, spyware or adware providers to track personal information.
Cookies are NOT a "threat" in the typical sense we think of malware infection. As text files, cookies are inherently harmless and cannot be executed to cause any damage. Cookies do not cause any pop ups or install malware and they cannot erase or read information from a computer.
Cookies cannot be used to run code (run programs) or to deliver viruses to your computer. The purpose of a cookie is to tell the Web server that you have returned to a specific Web page.
Microsoft's Description of Cookies
Cookies are short pieces of data used by web servers to help identify web users. The popular concepts and rumors about what a cookie can do has reached almost mystical proportions, frightening users and worrying their managers.
Do cookies pose a security risk?
The primary purpose of cookies is to identify users and prepare customized web pages for them. There are two different types of cookies.
- Persistent cookies have expiration dates set by the Web server when it passes the cookie and are stored on a user's hard drive until they expire or are deleted. These types of cookies are used to store information between visits to a site and collect identifying information about the user such as surfing behavior or preferences for a specific web site.
- Session cookies (transient or Non-persistent cookies) cookies are not saved to the hard drive, do not collect any information and have no set expiration date. They are used to temporarily hold information in the form of a session identification stored in memory as you browse web pages. These types of cookies are cached only while a user is visiting the Web server issuing the session cookie and are deleted from the cache when the user closes the session.
Cookies can be categorized as:
- Trusted cookies are from sites you trust, use often, and want to be able to identify and personalize content for you.
- Nuisance cookies are from those sites you do not recognize or often use but somehow it's put a cookie on your machine.
- Bad cookies (i.e. persistent cookies, long term and third party tracking cookies) are those that can be linked to an ad company or something that tracks your movements across the web.
The type of persistent cookie that is a cause for some concern are "tracking cookies" because they can be considered a privacy risk. These types of cookies are used to track your Web browsing habits...your movement from site to site. Ad companies use them to record your activity on all sites where they have placed ads. They can keep count of how many times you visited a web page, store your username and password so you don't have to log in and retain your custom settings. When you visit one of these sites, a cookie is placed on your computer. Each time you visit another site that hosts one of their ads, that same cookie is read, and soon they have assembled a list of which of their sites you have visited and which of their ads that you have clicked on. Cookies are used all over the Internet and advertisement companies often plant them whenever your browser loads one of their banners.
Flash cookies (or Local Shared Objects) and Evercookies are a newer way of tracking user behavior and surfing habits but they too are not a threat, and cannot harm your computer.
Flash cookies are cookie-like data stored on a computer and used by all versions of Adobe Flash Player and similar applications. They can store much more information than traditional browser cookies and they are typically stored within each user’s Application Data directory with a ".SOL" extension, under the Macromedia\FlashPlayer\#SharedObjects folder. Unlike traditional cookies, Flash cookies cannot be managed through browser controls so they are more difficult to find and remove. However, they can be viewed, managed and deleted using the Website Storage Settings panel at Macromedia's Support Site. From this panel, you can change storage settings for a website, delete a specific website or delete all sites which erases any information that may have been stored on the computer. To prevent any Flash Cookies from being stored on your computer, go to the Global Storage Settings panel and uncheck the option “Allow third-party Flash content to store data on your computer”. For more information, please refer to:
However, new research has disclosed that cookies can be used to allow remote attackers to bypass a secure protocol (HTTPS) and reveal private session information, and that modern browsers currently provide no protection against the attack vector. A cookie injection attack can be mounted by man-in-the-middle attackers who set cookies throughout their invasive session allowing them to facilitate the disclosure of any private data being transmitted in the session.
As long as you surf the Internet, you are going to get cookies and some of your security programs will flag them for removal. Anti-malware scanners have more important things to look for, so I would recommend disabling the option to search for cookies which will also decrease the amount of time it takes to perform a scan. You can minimize the number of cookies which are stored on your computer by using tools like SpywareBlaster, WinPatrol’s Cookie Manager and Ghostery, a browser tool which allows you to block beacons, trackers, advertising, analytics, widgets and cookies.
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