CVE-2020-27387

HIGH EXPLOITED

HorizontCMS <1.0.0-beta - Code Injection

Title source: llm
STIX 2.1

Exploitation Summary

CVE-2020-27387 has been observed exploited in the wild (reported by VulnCheck KEV). EIP tracks 1 public exploit from researchers including Erik Wynter, including a Metasploit module exploits/multi/http/horizontcms_upload_exec.

AI-analyzed exploit summary This Metasploit module exploits an arbitrary file upload vulnerability in HorizontCMS 1.0.0-beta to execute arbitrary commands by uploading a malicious PHP file and renaming it to bypass server-side restrictions.

Description

An unrestricted file upload issue in HorizontCMS through 1.0.0-beta allows an authenticated remote attacker (with access to the FileManager) to upload and execute arbitrary PHP code by uploading a PHP payload, and then using the FileManager's rename function to provide the payload (which will receive a random name on the server) with the PHP extension, and finally executing the PHP file via an HTTP GET request to /storage/<php_file_name>. NOTE: the vendor has patched this while leaving the version number at 1.0.0-beta.

Exploits (1)

metasploit WORKING POC EXCELLENT
by Erik Wynter · rubypocphp
https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/multi/http/horizontcms_upload_exec.rb

This Metasploit module exploits an arbitrary file upload vulnerability in HorizontCMS 1.0.0-beta to execute arbitrary commands by uploading a malicious PHP file and renaming it to bypass server-side restrictions.

Classification
Working Poc 100%
Attack Type
Rce
Complexity
Moderate
Reliability
Reliable
Target: HorizontCMS 1.0.0-beta
Auth required
Prerequisites: Valid credentials for a HorizontCMS user with FileManager permissions · Network access to the target
devstral-2 · analyzed Feb 16, 2026 Full analysis →

References (4)

Core 4
Core References
Third Party Advisory x_refsource_misc
https://github.com/rapid7/metasploit-framework/pull/14340
Exploit, Patch, Third Party Advisory x_refsource_misc
https://blog.vonahi.io/whats-in-a-re-name/
Exploit, Third Party Advisory, VDB Entry x_refsource_misc
http://packetstormsecurity.com/files/160046/HorizontCMS-1.0.0-beta-Shell-Upload.html

Scores

CVSS v3 8.8
EPSS 0.7032
EPSS Percentile 98.7%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Details

VulnCheck KEV 2025-07-13
CWE
CWE-434
Status published
Products (1)
horizontcms_project/horizontcms 1.0.0 alpha (9 CPE variants)
Published Nov 05, 2020
Tracked Since Feb 18, 2026