Release Date: June 16, 2009
Component Type: Third party extension. This extension is not a part of the TYPO3 default installation.
Affected Versions: Version 2.7.1 and all versions below
Vulnerability Type: Cross-Site Scripting
Problem Description: Failing to filter user input the extension is open to Cross-Site Scripting.
Solution: An updated version 2.7.2 is available from the TYPO3 extension manager and at http://typo3.org/extensions/repository/view/ve_guestbook/2.7.2/. Users of the extension are advised to update the extension as soon as possible.
Credits: Credits go to Alexander Kellner who discovered and reported the issue.