An XSS issue was discovered in Horde Groupware Webmail Edition through 5.2.22 (where the Horde_Text_Filter library before 2.3.7 is used). The attacker can send a plain text e-mail message, with JavaScript encoded as a link or email that is mishandled by preProcess in Text2html.php, because bespoke use of \x00\x00\x00 and \x01\x01\x01 interferes with XSS defenses.

Text_Filter/lib/Horde/Text/Filter/Xss.php in Horde Application Framework before 3.3.6, Horde Groupware before 1.2.5, and Horde Groupware Webmail Edition before 1.2.5 does not properly handle data: URIs, which allows remote attackers to conduct cross-site scripting (XSS) attacks via data:text/html values for the HREF attribute of an A element in an HTML e-mail message. NOTE: the vendor states that the issue is caused by "an XSS vulnerability in Firefox browsers."

Multiple cross-site scripting (XSS) vulnerabilities in the administration interface in Horde Application Framework before 3.3.6, Horde Groupware before 1.2.5, and Horde Groupware Webmail Edition before 1.2.5 allow remote attackers to inject arbitrary web script or HTML via the PATH_INFO to (1) phpshell.php, (2) cmdshell.php, or (3) sqlshell.php in admin/, related to the PHP_SELF variable.

The form library in Horde Application Framework 3.2 before 3.2.5 and 3.3 before 3.3.5; Groupware 1.1 before 1.1.6 and 1.2 before 1.2.4; and Groupware Webmail Edition 1.1 before 1.1.6 and 1.2 before 1.2.4; reuses temporary filenames during the upload process which allows remote attackers, with privileges to write to the address book, to overwrite arbitrary files and execute PHP code via crafted Horde_Form_Type_image form field elements.

The image view functionality in Horde Groupware Webmail Edition before 5.2.22 is affected by a stored Cross-Site Scripting (XSS) vulnerability via an SVG image upload containing a JavaScript payload. An attacker can obtain access to a victim's webmail account by making them visit a malicious URL.