What is CVE-2020-21357?

CVE-2020-21357 is a medium-severity vulnerability in Popojicms, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2021-08-06.

How severe is CVE-2020-21357?

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

XSS in Popojicms

CVE-2020-21357

A stored cross site scripting (XSS) vulnerability in /admin.php?mod=user&act=addnew of PopojiCMS 1.2 allows attackers to execute arbitrary web scripts or HTML via a crafted payload in the E-Mail field.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2021-08-06 · 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 (54.2th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 54th percentile — 54.2% 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

Popojicms — versions 1.2

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

github.com/PopojiCMS/PopojiCMS/issues/24 (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2020-21357?: CVE-2020-21357 is a medium-severity vulnerability in Popojicms, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2021-08-06.
How severe is CVE-2020-21357?: Medium severity. CVSS v3 base score is 6.1 out of 10.