Evercookie: The Persistent Tracking Mechanism - Decisimo

Evercookie is a JavaScript-based tracking mechanism that creates extremely persistent cookies in a browser. This article explores how Evercookie works, its value for tracking users, its limitations, and how users can protect themselves.

What is an Evercookie?

An Evercookie is a type of tracking cookie that uses multiple storage mechanisms to persistently store data on a user’s browser. Unlike regular cookies, Evercookies are designed to be extremely difficult to delete and are able to rebuild themselves even after being removed.

How Does Evercookie Work?

1. Storing Data in Multiple Places: Evercookie stores the same piece of data in various storage mechanisms available in the browser, such as standard HTTP cookies, Local Shared Objects (Flash cookies), and HTML5 storage.
2. Rebuilding Mechanism: If any of the stored data is deleted, Evercookie uses the remaining data to recreate and repopulate the deleted storage mechanisms.
3. Persistent Tracking: Through this persistent storage and rebuilding mechanism, Evercookie enables long-term user tracking.

Value of Evercookie for Tracking

Evercookie is valuable for tracking purposes due to its:

• Persistence: It remains on the user’s browser even after attempts to delete it.
• Cross-Session Tracking: It can track users across multiple browsing sessions.
• Resistance to Blocking: Traditional cookie blockers may not be effective against Evercookie.

Limitations of Evercookie

• Privacy Concerns: The persistent nature of Evercookie raises serious privacy concerns and may be considered invasive.
• Regulatory Restrictions: Some jurisdictions have legal restrictions on the use of tracking technologies like Evercookie.
• Browser Support: Not all browsers support the storage mechanisms used by Evercookie.

Protecting Against Evercookie

There are several methods to protect against the Evercookie:

• Using Privacy-focused Browsers: Browsers like Tor or those with enhanced privacy settings can help protect against Evercookie.
• Disabling Flash and Other Plugins: Disabling plugins that Evercookie might use for storage can limit its effectiveness.
• Regularly Clearing Browser Data: Regularly clearing all browser data, including cookies and other storage mechanisms, can help in mitigating the persistence of Evercookie.

Conclusion

Evercookie is a powerful tracking mechanism that poses significant privacy challenges. Understanding its workings and taking protective measures are essential for users who wish to maintain control over theironline browsing data and privacy.

Published: 2023-04-26