CVE-2020-8866

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 9.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2020-03-23 · updated 2026-06-17
Weakness: CWE-434

Description

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.

Affected products

Debian Linux: 8.0
Horde Groupware: 5.2.22
Horde Form: before 2.0.20 — fixed in 2.0.20

How to fix

Upgrade to a fixed version: Horde Form 2.0.20. Check the vendor advisory for mitigations.

References

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