CVE-2026-15965
Medium
Elevated severity or exploit probability.
CVSS base
8.8
HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS — probability of exploitation (30 days)
1.0%
62.0th percentile
CISA KEV
Not listed
Weakness / dates
CWE-434
Published 2026-08-15 · modified 2026-08-20
Description
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.
References
- https://plugins.trac.wordpress.org/browser/maxupload-upload-larger-files-easily/tags/1.4.0/includes/uploader.php#L121
- https://plugins.trac.wordpress.org/browser/maxupload-upload-larger-files-easily/tags/1.4.0/includes/uploader.php#L174
- https://plugins.trac.wordpress.org/browser/maxupload-upload-larger-files-easily/tags/1.4.0/includes/uploader.php#L19
- https://plugins.trac.wordpress.org/browser/maxupload-upload-larger-files-easily/tags/1.4.0/includes/uploader.php#L201
- https://plugins.trac.wordpress.org/browser/maxupload-upload-larger-files-easily/tags/1.4.0/maxupload-wp.php#L88
- https://www.wordfence.com/threat-intel/vulnerabilities/id/70d90c0c-e3c6-4db9-b16d-1442e7e1dc3b?source=cve