CVE-2021-4356Public exploitNetwork attack vector

Unauthenticated file download via arbitrary post metadata

Published Jun 7, 2023 · Updated Apr 8, 2026

Missing authorization in N-Media Frontend File Manager Plugin before 18.3 allows remote attackers to download arbitrary server files. The unauthenticated wpfm_file_meta_update AJAX action accepts a caller-selected post ID and writes unsanitized request keys as post metadata, letting wpfm_dir_path point to wp-config.php. Network access to a WordPress site running the plugin is sufficient, and disclosure of configuration secrets can enable site takeover.

CVSS severity9.0
Critical
EPSS probability1.52%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in N-Media Frontend File Manager Plugin before 18.3 allows remote attackers to download arbitrary server files. The unauthenticated wpfm_file_meta_update AJAX action accepts a caller-selected post ID and writes unsanitized request keys as post metadata, letting wpfm_dir_path point to wp-config.php. Network access to a WordPress site running the plugin is sufficient, and disclosure of configuration secrets can enable site takeover.

The record

CVE
CVE-2021-4356
Published
Jun 7, 2023
Updated
Apr 8, 2026
Vendor
N-Media
Product
Frontend File Manager Plugin
Classifications
CWE-862, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 7, 2023CVE publishedPublication date reported by the CVE source.
  2. Apr 8, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <18.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

N-Media · Frontend File Manager Pluginversion=0 <18.3

Published CVSS scores

9.0WordfenceCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
9.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-862Missing Authorization
T1190Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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