A browser cookie that won't go away?

The evercookie produces "extremely persistent cookies" that can identify a client even after you've removed standard or Flash cookies

"Evercookie" is the browser cookie that just won't go away. If you're concerned about having your Web browsing history tracked, you, like most people, will probably delete your cookies and clear your browsers' caches. However, evercookie, written in JavaScript, produces "extremely persistent cookies" that can identify a client even after you've removed standard or Flash cookies.

How does evercookie work? It stores cookie data in several different manners in your browser, including HTTP, Flash, force-cached PNG images, various HTML5 storage systems, web history, and SQLite. If evercookie detects that you've been deleting your cookies, the program recreates your cookies.

Created by Samy Kamkar (who spawned a MySpace worm in 2005), evercookie was built in one day to make people more aware of the privacy issues inherent in tracking cookies, whether traditional HTML or Flash, according to threatpost.com. Want to experiment with evercookie on your own? The code is open source, and available at Kamkar's Website so that you can install it on your own webserver.

At present, one of the ways around evercookie's persistence is Safari's Private Browsing feature, which blocks all of evercookie's methods. Other browsers might stand up to evercookie's means of keeping cookies around, though Kamkar has not performed exhaustive testing. What's a user to do? Be careful about which browsers you accept cookies from, and keep tabs on HTML5 as it is developed. Some criticize the HTML5 standard for emphasizing functionality rather than security, something that evercookie exploits.

[via Threatpost]

More security nerdery from PCWorld's GeekTech blog:

* Lawsuit: Ad Network Could Be Tracking You With HTML5

* RIAA, MPAA Websites Pummeled By 4chan's Wrath

* Adobe Warns Acrobat Users: Don't Install Third-Party Security Patch

Follow Alessondra Springmann and GeekTech on Twitter.

Join the newsletter!

Or

Sign up to gain exclusive access to email subscriptions, event invitations, competitions, giveaways, and much more.

Membership is free, and your security and privacy remain protected. View our privacy policy before signing up.

Error: Please check your email address.

Tags browsersinternetsoftwareapplications

Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Alessondra Springmann

PC World (US online)
Show Comments

Brand Post

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Luke Hill

MSI GT75 TITAN

I need power and lots of it. As a Front End Web developer anything less just won’t cut it which is why the MSI GT75 is an outstanding laptop for me. It’s a sleek and futuristic looking, high quality, beast that has a touch of sci-fi flare about it.

Emily Tyson

MSI GE63 Raider

If you’re looking to invest in your next work horse laptop for work or home use, you can’t go wrong with the MSI GE63.

Laura Johnston

MSI GS65 Stealth Thin

If you can afford the price tag, it is well worth the money. It out performs any other laptop I have tried for gaming, and the transportable design and incredible display also make it ideal for work.

Andrew Teoh

Brother MFC-L9570CDW Multifunction Printer

Touch screen visibility and operation was great and easy to navigate. Each menu and sub-menu was in an understandable order and category

Louise Coady

Brother MFC-L9570CDW Multifunction Printer

The printer was convenient, produced clear and vibrant images and was very easy to use

Edwina Hargreaves

WD My Cloud Home

I would recommend this device for families and small businesses who want one safe place to store all their important digital content and a way to easily share it with friends, family, business partners, or customers.

Featured Content

Product Launch Showcase

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?