HIGH

CVE-2019-9858

CVSS v3

8.8

HIGH

EPSS Score

80.4%

exploit probability

CISA KEV

No

known exploited

Exploitation

SSVC status

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.)

Technical details

Published
5/29/2019

Frequently asked questions

What is 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.)

Is CVE-2019-9858 actively exploited?

Active exploitation of CVE-2019-9858 has not been confirmed. The EPSS score is 80.4%, indicating the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2019-9858?

CVE-2019-9858 has a CVSS v3 base score of 8.8 (HIGH severity).

Is CVE-2019-9858 affecting your environment?

Use isMalicious to check if any of your IPs or domains are associated with this vulnerability's IOCs.