Cross-site scripting (XSS) vulnerability in the frontend plugin for the felogin system extension in TYPO3 4.2.0, 4.2.1 and 4.2.2 allows remote attackers to inject arbitrary web script or HTML via unknown vectors.
The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.