What is CVE-2020-22421?

CVE-2020-22421 is a medium-severity vulnerability in 74cms, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2021-12-08.

How severe is CVE-2020-22421?

Medium severity. CVSS v3 base score is 6.1 out of 10.

Is CVE-2020-22421 known to be exploited?

2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

XSS in 74cms

CVE-2020-22421

74CMS v6.0.4 was discovered to contain a cross-site scripting (XSS) vulnerability via /index.php?m=&c=help&a=help_list&key.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2021-12-08 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.008 (54.9th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 55th percentile — 54.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000

Affected products

74cms — versions 6.0.4

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

Public proof-of-concept exploits

References

github.com/congcong9184-123/congcong9184-123.github.io/blob/master/74cms.docx (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2020-22421?: CVE-2020-22421 is a medium-severity vulnerability in 74cms, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2021-12-08.
How severe is CVE-2020-22421?: Medium severity. CVSS v3 base score is 6.1 out of 10.
Is CVE-2020-22421 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.