CVE-2021-4356: Frontend File Manager <= 18.2 - Unauthenticated Arbitrary File Download

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.5% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2023-06-07 · updated 2026-06-17
Weakness: CWE-862

Description

The Frontend File Manager plugin for WordPress is vulnerable to Unauthenticated Arbitrary File Download in versions up to, and including, 18.2. This is due to lacking authentication protections, capability checks, and sanitization, all on the wpfm_file_meta_update AJAX action. This makes it possible for unauthenticated attackers to download arbitrary files on the site, potentially leading to site takeover.

Affected products

nmedia Frontend File Manager Plugin: through 18.2

References

https://blog.nintechnet.com/wordpress-frontend-file-manager-plugin-fixed-multiple-critical-vulnerabilities/
https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=2554359%40nmedia-user-file-uploader&new=2554359%40nmedia-user-file-uploader&sfp_email=&sfph_mail=
https://www.wordfence.com/threat-intel/vulnerabilities/id/79e2011c-5e4d-4d02-831f-6b4dcfcaa51e?source=cve
https://blog.nintechnet.com/wordpress-frontend-file-manager-plugin-fixed-multiple-critical-vulnerabilities/
https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=2554359%40nmedia-user-file-uploader&new=2554359%40nmedia-user-file-uploader&sfp_email=&sfph_mail=
https://www.wordfence.com/threat-intel/vulnerabilities/id/79e2011c-5e4d-4d02-831f-6b4dcfcaa51e?source=cve

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