What is CVE-2020-20699?

CVE-2020-20699 is a medium-severity vulnerability in S-Cms, classified under Cross-site Scripting. CVSS score: 4.8/10. Published 2021-07-30.

How severe is CVE-2020-20699?

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

XSS in S-Cms

CVE-2020-20699

A cross site scripting (XSS) vulnerability in S-CMS PHP v3.0 allows attackers to execute arbitrary web scripts or HTML via a crafted payload entered into the Copyright text box under Basic Settings.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2021-07-30 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 4.8 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.005 (42.4th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 42.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

S-Cms — versions 3.0

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

github.com/Peithon/xss/blob/master/readme.md (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2020-20699?: CVE-2020-20699 is a medium-severity vulnerability in S-Cms, classified under Cross-site Scripting. CVSS score: 4.8/10. Published 2021-07-30.
How severe is CVE-2020-20699?: Medium severity. CVSS v3 base score is 4.8 out of 10.