Horde 3.3.12, Horde Groupware 1.2.10, and Horde Groupware Webmail Edition 1.2.10, as distributed by FTP between November 2011 and February 2012, contains an externally introduced modification (Trojan Horse) in templates/javascript/open_calendar.js, which allows remote attackers to execute arbitrary PHP code.

Cross-site scripting (XSS) vulnerability in Horde_Form in Horde Groupware Webmail Edition before 4.0.6 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors, related to email verification. NOTE: Some of these details are obtained from third party information.

Multiple cross-site scripting (XSS) vulnerabilities in Horde IMP before 5.0.18 and Horde Groupware Webmail Edition before 4.0.6 allow remote attackers to inject arbitrary web script or HTML via the (1) composeCache, (2) rtemode, or (3) filename_* parameters to the compose page; (4) formname parameter to the contacts popup window; or (5) IMAP mailbox names. NOTE: some of these details are obtained from third party information.

The _bad_protocol_once function in phpgwapi/inc/class.kses.inc.php in KSES, as used in eGroupWare before 1.4.003, Moodle before 1.8.5, and other products, allows remote attackers to bypass HTML filtering and conduct cross-site scripting (XSS) attacks via a string containing crafted URL protocols.