PayPal Fixes Critical Account Switching Bug
 

A security researcher alerted PayPal to a flaw that would allow a malicious user to take over a user's account by using just a few simple manuevers on the hijacked account. The bug was reported as part of the PayPal Bounty Program, saving PayPal untold sums of hacked account repayments.

http://www.hardocp.com/news/2013/08/...switching_bug/