CVE-2019-9858

Remote code execution was discovered in Horde Groupware Webmail 5.2.22 and
5.2.17. Horde/Form/Type.php contains a vulnerable class that handles image
upload in forms. When the Horde_Form_Type_image method onSubmit() is called
on uploads, it invokes the functions getImage() and _getUpload(), which
uses unsanitized user input as a path to save the image. The unsanitized
POST parameter object[photo][img][file] is saved in the $upload[img][file]
PHP variable, allowing an attacker to manipulate the $tmp_file passed to
move_uploaded_file() to save the uploaded file. By setting the parameter to
(for example) …/usr/share/horde/static/bd.php, one can write a PHP
backdoor inside the web root. The static/ destination folder is a good
candidate to drop the backdoor because it is always writable in Horde
installations. (The unsanitized POST parameter went probably unnoticed
because it’s never submitted by the forms, which default to securely using
a random path.)

Bugs

• <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=930321&gt;