CVE-2025-2801: WordPress Smart Forms Plugin RCE Vulnerability

CVE-2025-2801 Overview

The ABCSubmit plugin for WordPress (Create custom forms for WordPress with a smart form plugin for smart businesses) contains an arbitrary shortcode execution vulnerability affecting all versions up to and including 1.2.4. The vulnerability stems from improper input validation when processing user-supplied values before passing them to the do_shortcode function. This flaw allows unauthenticated attackers to execute arbitrary WordPress shortcodes, potentially leading to information disclosure, site manipulation, or further exploitation depending on other installed plugins.

Critical Impact

Unauthenticated attackers can execute arbitrary WordPress shortcodes without authentication, potentially compromising site integrity and accessing sensitive functionality exposed through shortcode handlers.

Affected Products

• ABCSubmit WordPress Plugin version 1.2.4 and earlier
• WordPress sites utilizing the ABCSubmit form builder plugin
• Self-hosted WordPress installations with vulnerable plugin versions

Discovery Timeline

• 2025-04-26 - CVE-2025-2801 published to NVD
• 2025-04-29 - Last updated in NVD database

Technical Details for CVE-2025-2801

Vulnerability Analysis

This vulnerability is classified under CWE-94 (Improper Control of Generation of Code - Code Injection). The ABCSubmit plugin fails to properly validate user-controlled input before passing it to WordPress's do_shortcode() function. In WordPress, shortcodes are bracketed expressions that execute registered handler functions, and when arbitrary shortcode execution is possible, attackers can invoke any shortcode registered on the system.

The attack surface is particularly concerning because it requires no authentication. An unauthenticated remote attacker can craft malicious requests that trigger shortcode execution, potentially leveraging shortcodes from other installed plugins that may perform sensitive operations such as database queries, file operations, or administrative functions.

Root Cause

The root cause lies in the plugin's failure to implement proper input validation and sanitization before calling do_shortcode(). The vulnerable code paths exist in abcsubmit.php at lines 86 and 88, where user-supplied data flows directly into the shortcode execution function without adequate filtering or whitelisting of allowed shortcode tags.

WordPress shortcodes are designed for trusted content authors, not for processing untrusted user input. By allowing arbitrary shortcode strings from unauthenticated users, the plugin creates a code injection pathway that violates the principle of least privilege.

Attack Vector

The vulnerability is exploitable over the network without requiring authentication or user interaction. An attacker can send specially crafted HTTP requests to the WordPress site containing malicious shortcode syntax. The attack methodology involves:

1. Identifying WordPress sites running the vulnerable ABCSubmit plugin
2. Crafting requests with attacker-controlled shortcode strings
3. Submitting these requests to trigger the vulnerable code path
4. Executing arbitrary shortcodes registered on the target site

The impact depends heavily on what other plugins are installed and what shortcodes they register. In environments with plugins that expose database operations, file management, or administrative functions via shortcodes, the potential for damage escalates significantly.

For technical details on the vulnerable code paths, refer to the ABCSubmit plugin source code on WordPress Trac and the Wordfence vulnerability analysis.

Detection Methods for CVE-2025-2801

Indicators of Compromise

• Unusual HTTP requests containing bracket notation [shortcode] patterns in form submission parameters
• Web server access logs showing POST requests to ABCSubmit endpoints with suspicious payloads
• Unexpected shortcode execution artifacts in WordPress debug logs
• Evidence of shortcode-based operations from unauthenticated sessions

Detection Strategies

• Monitor web application firewall (WAF) logs for requests containing shortcode syntax patterns targeting form endpoints
• Implement regex-based detection rules for shortcode bracket patterns in untrusted input fields
• Review WordPress activity logs for shortcode execution events from non-authenticated contexts
• Deploy file integrity monitoring to detect changes resulting from malicious shortcode execution

Monitoring Recommendations

• Enable WordPress debug logging temporarily to capture shortcode execution patterns during incident investigation
• Configure WAF rules to alert on bracket notation patterns in POST data targeting plugin endpoints
• Implement rate limiting on form submission endpoints to slow automated exploitation attempts
• Monitor for anomalous database queries that may result from shortcode abuse

How to Mitigate CVE-2025-2801

Immediate Actions Required

• Update the ABCSubmit plugin to a patched version immediately if available
• Temporarily deactivate the ABCSubmit plugin if no patch is available until a fix is released
• Review WordPress site for signs of compromise or unauthorized shortcode execution
• Audit installed plugins for sensitive shortcodes that could be abused if executed by attackers

Patch Information

Check the ABCSubmit plugin developer page for the latest version containing security fixes. Ensure automatic plugin updates are enabled or establish a regular patching schedule for WordPress plugins.

Organizations should verify the plugin version currently installed by navigating to the WordPress admin panel under Plugins and confirming the ABCSubmit version number is higher than 1.2.4.

Workarounds

• Deactivate the ABCSubmit plugin until a patched version is available
• Implement WAF rules to block requests containing shortcode bracket patterns in form submissions
• Use WordPress security plugins to restrict shortcode execution to authenticated administrators only
• Consider alternative form plugins that implement proper input validation and shortcode restrictions

# WordPress CLI command to deactivate the vulnerable plugin
wp plugin deactivate abcsubmit

# Verify current plugin version
wp plugin get abcsubmit --field=version

# Check for available updates
wp plugin update abcsubmit --dry-run