What is CVE-2021-42335?

CVE-2021-42335 is a medium-severity vulnerability in Huachu Digital Technology Co.,ltd. Easytest, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2021-10-15.

How severe is CVE-2021-42335?

Medium severity. CVSS v3 base score is 5.4 out of 10.

XSS in Huachu Digital Technology Co.,ltd. Easytest

CVE-2021-42335

Easytest bulletin board management function of online learning platform does not filter special characters. After obtaining a user’s privilege, remote attackers can inject JavaScript and execute stored XSS attack.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2021-10-15 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.006 (46.1th percentile), scored 2026-10-05.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 46th percentile — 46.1% 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

Huachu Digital Technology Co.,ltd. Easytest — versions 1705
Huaju Easytest Online Learning Test Platform — versions 1705

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

www.twcert.org.tw/tw/cp-132-5206-3cd3f-1.html (Third Party Advisory)

Frequently asked questions

What is CVE-2021-42335?: CVE-2021-42335 is a medium-severity vulnerability in Huachu Digital Technology Co.,ltd. Easytest, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2021-10-15.
How severe is CVE-2021-42335?: Medium severity. CVSS v3 base score is 5.4 out of 10.