Cross-site scripting (XSS) vulnerability in phpBB 2.0.19, when "Allowed HTML tags" is enabled, allows remote attackers to inject arbitrary web script or HTML via a permitted HTML tag with ' (single quote) characters and active attributes such as onmouseover, a variant of CVE-2005-4357.
Improper Neutralization of Input During Web Page Generation 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.