CVE-2026-15965

What it is

The MaxUpload – Big File Uploads – Increase Maximum File Upload Size plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 1.4.0 via the handle_upload function. This is due to a filename-validation mismatch in the handle_upload function where extension and MIME checks are applied to the uploaded chunk's filename but not to the final assembled filename derived from the resumableFilename parameter. This makes it possible for unauthenticated attackers to upload files that may be executable, which makes remote code execution possible.

At a glance

Exploitability

Can be exploited over the network with a low-privilege account. High risk of data exposure, data tampering, service disruption.

Exploit odds

1.0% chance of exploitation in the next 30 days (EPSS).

Fix

No patch or advisory is linked yet. Look at mitigations or restrict exposure.

Timeline

1. 2026-08-15 03:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-08-20 12:48 UTC Last updatedMost recent change to the record

Details

Published

2026-08-15 03:16 UTC

Last modified

2026-08-20 12:48 UTC

Exploit probability

1.0% · EPSS, next 30 days

Weakness

CWE-434 · Unrestricted file upload

Record status

Deferred

Attack profile CVSS 3.1 · 8.8

Attack vector

Network

Complexity

Low

Privileges needed

Low

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High