What is CVE-2021-33387?

CVE-2021-33387 is a critical-severity vulnerability in 1234n Minicms, classified under Cross-site Scripting. CVSS score: 9.6/10. Published 2023-02-24.

How severe is CVE-2021-33387?

Critical severity. CVSS v3 base score is 9.6 out of 10.

XSS in 1234n Minicms

CVE-2021-33387

Cross Site Scripting Vulnerability in MiniCMS v.1.10 allows attacker to execute arbitrary code via a crafted get request.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2023-02-24 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.6 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.008 (56.1th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 56th percentile — 56.1% 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

1234n Minicms — versions 1.10

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

github.com/bg5sbk/MiniCMS/issues/40 (Exploit, Issue Tracking)

Frequently asked questions

What is CVE-2021-33387?: CVE-2021-33387 is a critical-severity vulnerability in 1234n Minicms, classified under Cross-site Scripting. CVSS score: 9.6/10. Published 2023-02-24.
How severe is CVE-2021-33387?: Critical severity. CVSS v3 base score is 9.6 out of 10.