Arbitrary file upload in Koken Cms

CVE-2020-37023

Koken CMS 0.22.24 contains a file upload vulnerability that allows authenticated attackers to bypass file extension restrictions by renaming malicious PHP files. Attackers can upload PHP files with system command execution capabilities by manipulating the file upload request through a web proxy and changing the file extension.

Vulnerability class: Unrestricted File Upload

EPSS: 0.006 (45.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2020-37023?
CVE-2020-37023 is a high-severity vulnerability in Koken Cms, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 8.8/10. Published 2026-01-30.
How severe is CVE-2020-37023?
High severity. CVSS v3 base score is 8.8 out of 10.