CVE-2023-4596Public exploitNetwork attack vector

Unauthenticated arbitrary upload via pre-validation file write

Published Aug 30, 2023 · Updated Apr 8, 2026

Unrestricted file upload in WPMU DEV Forminator 1.24.6 and earlier allows remote attackers to write arbitrary files to the server. The upload_post_image() function calls file_put_contents() before wp_check_filetype() validates the supplied filename and extension. A public Create Post form must allow unauthenticated submissions, and code execution follows only when the web server executes the uploaded file.

CVSS severity9.8
Critical
EPSS probability14.32%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Unrestricted file upload in WPMU DEV Forminator 1.24.6 and earlier allows remote attackers to write arbitrary files to the server. The upload_post_image() function calls file_put_contents() before wp_check_filetype() validates the supplied filename and extension. A public Create Post form must allow unauthenticated submissions, and code execution follows only when the web server executes the uploaded file.

The record

CVE
CVE-2023-4596
Published
Aug 30, 2023
Updated
Apr 8, 2026
Vendor
WPMU DEV
Product
Forminator
Classifications
CWE-434, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 30, 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 <=1.24.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

WPMU DEV · Forminatorversion=0 <=1.24.6

Published CVSS scores

9.8WordfenceCVSS: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.

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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-434Unrestricted Upload of File with Dangerous Type
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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