Arbitrary file upload in Horde Groupware

CVE-2020-8866

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.

Vulnerability class: Unrestricted File Upload

EPSS: 0.096 (95.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2020-8866?
CVE-2020-8866 is a medium-severity vulnerability in Horde Groupware, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 6.5/10. Published 2020-03-23.
How severe is CVE-2020-8866?
Medium severity. CVSS v3 base score is 6.5 out of 10.
Is CVE-2020-8866 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.