CVE-2008-1x3x

In this challenge, you are presented with the PHP function wp_validate_auth_cookie, which validates authentication cookies in WordPress. Initially, the function splits the cookie into three parts: username, expiration, and hmac, but without verifying the integrity of these parts. This oversight allows a malicious user to exploit the authentication mechanism by creating a username such as "admin1" and manipulating the expiration time, leading to potential unauthorized access.

The patch addresses this vulnerability by ensuring that the cookie is split into exactly three elements and by altering the way the hmac is generated. Instead of simply concatenating the username and expiration, the patch includes a delimiter to prevent collisions between similar usernames and different expiration times. This fix effectively mitigates the risk of unauthorized cookie manipulation.

This lab demonstrates the importance of rigorous validation and proper data handling in security-critical functions. By examining both the vulnerable code and the patch, you gain insights into common coding pitfalls and effective remediation strategies.