CVE-2021-4356 json
Frontend File Manager <= 18.2 - Unauthenticated Arbitrary File Download
published 3y ago modified 4mo ago also EUVD-2021-34183
- cvss
- 9.0
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.5%
- EPSS 1.5% chance of exploitation in 30 days, percentile 74%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- nmedia Frontend File Manager Plugin 18.3
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- last yr.
Exploit prediction
1.52% chance of exploitation in the next 30 days, higher than 74% of all scored CVEs (FIRST EPSS, 2026-11-09).
Exploits and checks
- blog.nintechnet.com https://blog.nintechnet.com/wordpress-frontend-file-manager-plugin-fixed-multiple-critical-vulnerabilities/ referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.0 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H |
| NVD | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Affected products
- nmedia Frontend File Manager Plugin
Classification
- Weakness
-
- CWE-862 Missing Authorization
- Technology feeds
References
-
plugins.trac.wordpress.org
/changeset?sfp_email=&sfph_mail=&reponame=&old=2554359%40nmedia-user-file-uploader&new=2554359%40nmedia-user-f
patch
-
blog.nintechnet.com
/wordpress-frontend-file-manager-plugin-fixed-multiple-critical-vulnerabilities/
exploit
-
wordfence.com
/threat-intel/vulnerabilities/id/79e2011c-5e4d-4d02-831f-6b4dcfcaa51e?source=cve
third-party-advisory
Sources
- CVE List CVE-2021-4356
- NVD CVE-2021-4356
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.