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Fencer Intel
medium 6.4

CVE-2021-4378 json

WP Quick FrontEnd Editor <= 5.5 - Authenticated (Subscriber+) Stored Cross-Site Scripting

published 3y ago modified 4mo ago also EUVD-2021-34205

cvss
6.4
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 42%
public exploits
0
none known

Summary

The WP Quick FrontEnd Editor plugin for WordPress is vulnerable to Stored Cross-Site Scripting in versions up to, and including, 5.5 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with minimal permissions like subscribers, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
last yr.

Exploit prediction

0.49% chance of exploitation in the next 30 days, higher than 42% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • blog.nintechnet.com https://blog.nintechnet.com/multiple-vulnerabilities-in-wordpress-wp-quick-frontend-editor-plugin-unpatched/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 6.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
NVD 3.1 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Affected products

  • labibahmed42 WP Quick FrontEnd Editor – WordPress Plugin

Classification

Weakness
  • CWE-79 Improper Neutralization of Input During Web Page Generation
Technology feeds

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.