CVE-2026-15550: Ninja Forms Save Progress Auth Bypass Flaw

CVE-2026-15550 Overview

The Ninja Forms - Save Progress plugin for WordPress contains a missing authorization vulnerability in versions up to and including 3.0.30. The bulk_actions function lacks capability checks and nonce verification. Authenticated attackers with subscriber-level access can delete arbitrary records from the wp_nf3_objects database table, including saved form submissions. The flaw is tracked under CWE-862: Missing Authorization.

Critical Impact
Any authenticated WordPress user with subscriber privileges or higher can delete saved form submissions and other records from the wp_nf3_objects table, causing data loss for site owners relying on Ninja Forms save-progress functionality.

Affected Products

Ninja Forms - Save Progress plugin for WordPress
All versions up to and including 3.0.30
WordPress installations with authenticated users at subscriber level or above

Discovery Timeline

2026-09-05 - CVE-2026-15550 published to NVD
2026-09-08 - Last updated in NVD database

Technical Details for CVE-2026-15550

Vulnerability Analysis

The vulnerability resides in the bulk_actions function of the Ninja Forms - Save Progress plugin. The function processes bulk operations against the wp_nf3_objects table without verifying that the requesting user holds the required capability. It also omits nonce validation, meaning the request is not tied to a legitimate administrative form submission.

An authenticated attacker with the lowest privilege role (subscriber) can invoke the vulnerable endpoint and issue delete operations against arbitrary rows. Saved form submissions, drafts, and other objects tracked in wp_nf3_objects are exposed to unauthorized removal. Impact is limited to integrity, as the flaw permits deletion but not confidential disclosure or full site takeover.

Root Cause

The root cause is a two-fold access control gap. First, the bulk_actions handler does not call a WordPress capability check such as current_user_can() to gate the operation to administrators. Second, it does not verify a nonce with check_admin_referer() or wp_verify_nonce(), so intent cannot be confirmed. The combination allows any logged-in user to reach a destructive database operation.

Attack Vector

Exploitation requires network access to the WordPress site and valid credentials for any account at subscriber level or above. The attacker sends a crafted request to the plugin's bulk action endpoint with delete parameters targeting rows in wp_nf3_objects. No user interaction from an administrator is required. Because subscriber registration is enabled on many WordPress deployments, the barrier to exploitation is low. See the Wordfence Vulnerability Report for advisory details.

No verified proof-of-concept code is available at this time. Refer to the Ninja Forms Save Progress Extension page for product context.

Detection Methods for CVE-2026-15550

Indicators of Compromise

Unexpected reductions in row count for the wp_nf3_objects table without corresponding administrator activity.
Web server access logs showing POST requests to Ninja Forms plugin endpoints from low-privilege user sessions.
Missing saved form submissions reported by end users or discovered during routine audits.

Detection Strategies

Enable WordPress database query logging or plugin audit logging to track DELETE statements affecting wp_nf3_objects.
Correlate authenticated session activity with plugin AJAX or admin-ajax.php requests referencing bulk action parameters.
Alert on any subscriber-level account issuing requests to Ninja Forms administrative handlers.

Monitoring Recommendations

Deploy a WordPress activity logging plugin that records data modification events with user attribution.
Baseline normal administrative traffic patterns and flag deviations from non-admin accounts.
Monitor for newly registered subscriber accounts that immediately interact with plugin endpoints.

How to Mitigate CVE-2026-15550

Immediate Actions Required

Update the Ninja Forms - Save Progress plugin to a version newer than 3.0.30 as soon as a patched release is available from the vendor.
Audit WordPress user accounts and remove unused subscriber-level accounts to reduce the attacker surface.
Back up the wp_nf3_objects table and related form submission data before applying updates or investigating suspicious activity.

Patch Information

Consult the vendor advisory at the Ninja Forms Save Progress Extension page and the Wordfence Vulnerability Report for updated version guidance. Apply the fixed release once published by Ninja Forms.

Workarounds

Disable the Ninja Forms - Save Progress plugin until a patched version is installed.
Restrict new user registration on WordPress sites that do not require public account creation.
Add a web application firewall rule to block requests to the plugin's bulk action endpoint from non-administrator sessions.

bash

# Disable open subscriber registration in wp-config.php or Settings > General
# Set default role to something restrictive and turn off open registration:
wp option update users_can_register 0
wp option update default_role subscriber

# Deactivate the vulnerable plugin via WP-CLI until patched
wp plugin deactivate ninja-forms-save-progress