CVE-2026-96649: Frontend Post Submission Manager Lite <= 1.3.4 - Unauthenticated Stored DOM-Based Cross-Site Scripting via post_content Parameter (data-label DOM Sink)
The Frontend Post Submission Manager Lite – Frontend Posting WordPress Plugin plugin for WordPress is vulnerable to Stored DOM-Based Cross-Site Scripting via postcontent Parameter (data-label DOM Sink) in all versions up to, and including, 1.3.4 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 site operator to have enabled guest post submission via the [fpsm] shortcode, which registers a publicly accessible AJAX handler gated only by a nonce emitted on every page containing the shortcode.
Affected Software
Event History
Frequently Asked Questions
Which sites are exposed to exploitation?
Sites using Frontend Post Submission Manager Lite version 1.3.4 or earlier are exposed if they have enabled guest post submission through the [fpsm] shortcode. The shortcode emits a nonce on each page where it appears and exposes the relevant AJAX handler publicly.
Does an attacker need an account or user interaction to inject the payload?
No. An unauthenticated attacker can submit the malicious post_content value when guest submission is enabled; a user later visiting the injected page triggers execution of the stored script.
What can be done while a patch is unavailable?
Disable guest post submission and remove or prevent public access to pages containing the [fpsm] shortcode. This removes the publicly accessible AJAX path described as necessary for exploitation.
How can I determine whether my site may already be affected?
Check whether the plugin is at version 1.3.4 or earlier and whether guest post submission is enabled through [fpsm]. Review content submitted through that feature for injected script payloads, particularly in post content.