What is CVE-2018-16731?

CVE-2018-16731 is a critical-severity vulnerability in Chshcms Cscms, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 9.8/10. Published 2018-09-08.

How severe is CVE-2018-16731?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Arbitrary file upload in Chshcms Cscms

CVE-2018-16731

CScms 4.1 allows arbitrary file upload by (for example) adding the php extension to the default filetype list (gif, jpg, png), and then providing a .php pathname within fileurl JSON data.

Vulnerability class: Unrestricted File Upload

Published 2018-09-08 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.015 (73.1th percentile), scored 2026-10-01.

Low probability of exploitation in the next 30 days, but still tracked. 73rd percentile — 73.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.015 · newest: 0.015 · change: 0.000

Affected products

Chshcms Cscms — versions 4.1

Weakness classification (CWE)

CWE-434 — Unrestricted Upload of File with Dangerous Type

References

github.com/AvaterXXX/CScms/blob/master/CScms_up.md (Third Party Advisory)
www.patec.cn/newsshow.php (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2018-16731?: CVE-2018-16731 is a critical-severity vulnerability in Chshcms Cscms, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 9.8/10. Published 2018-09-08.
How severe is CVE-2018-16731?: Critical severity. CVSS v3 base score is 9.8 out of 10.