What is CVE-2021-4363?

CVE-2021-4363 is a medium-severity vulnerability in Labibahmed42 Wp Quick Frontend Editor – WordPress Plugin, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2023-06-07.

How severe is CVE-2021-4363?

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

Is CVE-2021-4363 known to be exploited?

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

XSS in Labibahmed42 Wp Quick Frontend Editor – WordPress Plugin

CVE-2021-4363

The WP Quick FrontEnd Editor plugin for WordPress is vulnerable to Reflected Cross-Site Scripting in versions up to, and including, 5.5 due to insufficient input sanitization and output escaping on the 'save_content_front' function that uses print_r on the user-supplied $_REQUEST values . This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2023-06-07 · 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: 0.007 (52.9th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 53rd percentile — 52.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: -0.000

Affected products

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

Public proof-of-concept exploits

20142995/nuclei-templates

References

www.wordfence.com/threat-intel/vulnerabilities/id/7ce8ae7d-c2a5-4da3-8bdd-20dfd… (Third Party Advisory)
wordpress.org/plugins/wp-quick-front-end-editor/ (Product)
blog.nintechnet.com/multiple-vulnerabilities-in-wordpress-wp-quick-frontend-edi… (Exploit)

Frequently asked questions

What is CVE-2021-4363?: CVE-2021-4363 is a medium-severity vulnerability in Labibahmed42 Wp Quick Frontend Editor – WordPress Plugin, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2023-06-07.
How severe is CVE-2021-4363?: Medium severity. CVSS v3 base score is 6.1 out of 10.
Is CVE-2021-4363 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.