What is CVE-2020-18455?

CVE-2020-18455 is a medium-severity vulnerability in Bycms Project, classified under Cross-site Scripting. CVSS score: 4.8/10. Published 2021-08-12.

How severe is CVE-2020-18455?

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

XSS in Bycms Project

CVE-2020-18455

Cross Site Scripting (XSS) vulnerability exists in bycms v3.0.4 via the title parameter in the edit function in Document.php.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2021-08-12 · 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 (42.5th percentile), scored 2026-10-02.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 43rd percentile — 42.5% 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

Bycms Project — versions 1.3.0

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

github.com/hillerlin/bycms/issues/2 (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2020-18455?: CVE-2020-18455 is a medium-severity vulnerability in Bycms Project, classified under Cross-site Scripting. CVSS score: 4.8/10. Published 2021-08-12.
How severe is CVE-2020-18455?: Medium severity. CVSS v3 base score is 4.8 out of 10.