Cross-site scripting (XSS) vulnerability in Open Ticket Request System (OTRS) Help Desk 2.4.x before 2.4.14, 3.0.x before 3.0.16, and 3.1.x before 3.1.10, when Firefox or Opera is used, allows remote attackers to inject arbitrary web script or HTML via an e-mail message body with nested HTML tags.
http://znuny.com/en/#%21/advisory/ZSA-2012-02
http://www.otrs.com/de/open-source/community-news/security-advisories/security-advisory-2012-02/