Horde IMP through 6.2.27, as used with Horde Application Framework through 5.2.23, allows XSS that leads to account takeover via a crafted text/html e-mail message with an onerror attribute (that may use base64-encoded JavaScript code), as exploited in the wild in March 2025.

This vulnerability allows remote attackers to execute local PHP files on affected installations of Horde Groupware Webmail Edition 5.2.22. Authentication is required to exploit this vulnerability. The specific flaw exists within edit.php. When parsing the params[template] parameter, the process does not properly validate a user-supplied path prior to using it in file operations. An attacker can leverage this in conjunction with other vulnerabilities to execute code in the context of the www-data user. Was ZDI-CAN-10469.

This vulnerability allows remote attackers to create arbitrary files on affected installations of Horde Groupware Webmail Edition 5.2.22. Authentication is required to exploit this vulnerability. The specific flaw exists within add.php. The issue results from the lack of proper validation of user-supplied data, which can allow the upload of arbitrary files. An attacker can leverage this in conjunction with other vulnerabilities to execute code in the context of the www-data user. Was ZDI-CAN-10125.