What is CVE-2018-20017?

CVE-2018-20017 is a medium-severity vulnerability in Sem-Cms Semcms, classified under Cross-site Scripting. CVSS score: 4.8/10. Published 2018-12-10.

How severe is CVE-2018-20017?

Medium severity. CVSS v3 base score is 4.8 out of 10.

XSS in Sem-Cms Semcms

CVE-2018-20017

SEMCMS 3.5 has XSS via the first text box to the SEMCMS_Main.php URI.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2018-12-10 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 4.8 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.006 (44.4th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 44th percentile — 44.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

Sem-Cms Semcms — versions 3.5

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

github.com/source-trace/semcms/issues/1 (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2018-20017?: CVE-2018-20017 is a medium-severity vulnerability in Sem-Cms Semcms, classified under Cross-site Scripting. CVSS score: 4.8/10. Published 2018-12-10.
How severe is CVE-2018-20017?: Medium severity. CVSS v3 base score is 4.8 out of 10.