CVE-2026-100182: Download Monitor <= 5.2.10 - Unauthenticated Stored Cross-Site Scripting via Cross-Origin postMessage to Admin Editor
The Download Monitor plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Cross-Origin postMessage to Admin Editor in all versions up to, and including, 5.2.10 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This requires the attacker to trick an authenticated Administrator into visiting an attacker-controlled page that targets an open Download edit screen, after which the payload is persisted unfiltered via the Administrator's unfilteredhtml capability and later emitted verbatim to the frontend by the [downloaddata] shortcode's unescaped postcontent render path.
Affected Software
Event History
Frequently Asked Questions
Who is exposed to this issue?
Sites using Download Monitor version 5.2.10 or earlier are affected. Exploitation requires an authenticated WordPress Administrator to have a Download edit screen open and visit an attacker-controlled page.
Can an unauthenticated attacker exploit this without access to WordPress?
The attacker does not need WordPress credentials, but cannot complete the attack independently. They must induce an authenticated Administrator to visit a malicious page that sends a cross-origin postMessage to an open Download editor.
When does the injected script execute?
The payload is persisted through the Administrator's unfiltered_html capability and executes later when a user accesses an injected page. The affected rendering path is the [download_data] shortcode, which emits the stored post_content without escaping.