CVE-2026-18983: Wordpress Wp Handle Upload Missing Mimes

wp_handle_upload() or wp_handle_sideload() was called without specifying an allowed MIME types array ('mimes' in overrides). This allows WordPress default upload MIME types to be processed, which may lead to arbitrary file upload or stored XSS when unprivileged users are permitted to upload files.

Provally CuratedPublic repositoryMediumMedium confidenceVerifiedApache-2.0PHP
greprules fetch cve-2026-18983-wordpress-wp-handle-upload-missing-mimes --engine opengrep

Description

wp_handle_upload() or wp_handle_sideload() was called without specifying an allowed MIME types array ('mimes' in overrides). This allows WordPress default upload MIME types to be processed, which may lead to arbitrary file upload or stored XSS when unprivileged users are permitted to upload files.