CVE-2026-15965Public exploitNetwork attack vector

Unauthenticated code execution via unchecked assembled filename

Published Aug 15, 2026 · Updated Aug 15, 2026

Arbitrary file upload in MaxUpload 1.4.0 and earlier allows remote attackers to execute code via a crafted resumableFilename value. The handle_upload function checks each chunk's filename extension and MIME type but assembles the final file from resumableFilename without repeating those checks. No authentication is required; code execution occurs when the resulting uploaded file is executable by the WordPress host.

CVSS severity8.8
High
EPSS probability0.58%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Arbitrary file upload in MaxUpload 1.4.0 and earlier allows remote attackers to execute code via a crafted resumableFilename value. The handle_upload function checks each chunk's filename extension and MIME type but assembles the final file from resumableFilename without repeating those checks. No authentication is required; code execution occurs when the resulting uploaded file is executable by the WordPress host.

The record

CVE
CVE-2026-15965
Published
Aug 15, 2026
Updated
Aug 15, 2026
Vendor
Sadat Himel
Product
MaxUpload – Big File Uploads – Increase Maximum File Upload Size
Classifications
CWE-434, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 15, 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 <=1.4.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Sadat Himel · MaxUpload – Big File Uploads – Increase Maximum File Upload Sizeversion=0 <=1.4.0

Published CVSS scores

8.8WordfenceCVSS:3.1/AV:N/AC:L/PR:L/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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