CVE-2019-9858 Information

Description

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.)

CVSS Vector

CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Reference

http://packetstormsecurity.com/files/152476/Horde-Form-Shell-Upload.html https://lists.debian.org/debian-lts-announce/2019/06/msg00007.html https://seclists.org/bugtraq/2019/Jun/31 https://ssd-disclosure.com/?p=3814&preview=true https://www.debian.org/security/2019/dsa-4468

Attack Complexity

LOW

Privileges Required

LOW

User Interaction Required

LOW

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

8.8