CVE-2025-23862: Contact Form 7 Anti Spambot Auth Bypass

CVE-2025-23862 Overview

CVE-2025-23862 is a missing authorization vulnerability in the SzMake Contact Form 7 Anti Spambot WordPress plugin. The flaw affects all versions up to and including 1.0.1. The plugin exposes functionality without properly validating whether the requesting user holds the required capabilities, allowing unauthenticated attackers to reach access-controlled actions over the network.

The issue is classified under CWE-862: Missing Authorization. Exploitation requires no privileges and no user interaction. The impact is limited to availability, with no direct effect on confidentiality or integrity of stored data.

Critical Impact
Unauthenticated attackers can invoke plugin functionality that should require authorization, degrading availability of the affected WordPress site.

Affected Products

SzMake Contact Form 7 Anti Spambot plugin for WordPress
All versions from n/a through <= 1.0.1
WordPress installations with the contact-form-7-anti-spambot plugin active

Discovery Timeline

2025-01-16 - CVE CVE-2025-23862 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-23862

Vulnerability Analysis

The Contact Form 7 Anti Spambot plugin exposes one or more endpoints or actions without enforcing capability checks. WordPress plugins are expected to gate privileged operations behind current_user_can() checks and nonce validation via check_admin_referer() or wp_verify_nonce(). When those checks are missing, any unauthenticated visitor can trigger the underlying handler.

Because the CVSS vector reports no impact to confidentiality or integrity and only low impact to availability, the reachable functionality most likely toggles plugin state, resets configuration, or triggers resource-consuming operations rather than exposing sensitive data. The flaw is remotely triggerable and requires no authentication, which lowers the bar for opportunistic scanning and abuse.

Root Cause

The root cause is an incorrectly configured access control layer in the plugin's request handlers. The plugin registers actions or AJAX handlers that do not verify user capabilities before executing. This aligns with CWE-862, where the software fails to perform an authorization check when an actor attempts to access a resource or perform an action.

Attack Vector

An attacker sends a crafted HTTP request to the vulnerable endpoint exposed by the plugin on a target WordPress site. No credentials, session, or user interaction is required. Successful requests invoke plugin logic under the identity of the anonymous caller, producing an availability impact on the affected site. See the Patchstack Vulnerability Report for advisory details.

Detection Methods for CVE-2025-23862

Indicators of Compromise

Unauthenticated HTTP POST or GET requests to /wp-admin/admin-ajax.php or /wp-admin/admin-post.php referencing contact-form-7-anti-spambot actions
Unexpected changes to plugin settings or contact form spam-protection configuration
Bursts of requests to plugin-specific endpoints from a single IP or a small IP range
Requests to plugin handlers lacking the _wpnonce parameter

Detection Strategies

Enable WordPress request logging and alert on plugin AJAX actions invoked without an authenticated session cookie
Deploy a Web Application Firewall (WAF) rule that flags calls to contact-form-7-anti-spambot action names from unauthenticated sources
Monitor wp_options and plugin configuration tables for unauthorized modifications

Monitoring Recommendations

Track HTTP 200 responses to unauthenticated requests targeting plugin endpoints and correlate with configuration changes
Baseline normal request volumes to admin-ajax.php and alert on anomalous spikes
Forward WordPress and web server logs to a centralized SIEM for correlation and retention

How to Mitigate CVE-2025-23862

Immediate Actions Required

Update the Contact Form 7 Anti Spambot plugin to a version later than 1.0.1 once released by the vendor
If no patched version is available, deactivate and remove the plugin from all affected WordPress sites
Audit WordPress logs for prior unauthenticated access to plugin endpoints

Patch Information

At the time of publication, the Patchstack advisory lists versions <= 1.0.1 as affected with no fixed version identified. Monitor the plugin's page on the WordPress plugin directory for a security release.

Workarounds

Restrict access to /wp-admin/admin-ajax.php and /wp-admin/admin-post.php at the WAF or reverse proxy layer for anonymous callers where feasible
Add virtual patching rules to block requests referencing the vulnerable plugin action names until an official patch is applied
Replace the plugin with an alternative anti-spam solution such as the official Contact Form 7 integrations with reCAPTCHA or Akismet

bash

# Example WAF rule (ModSecurity) to block unauthenticated access to the plugin action
SecRule REQUEST_URI "@rx /wp-admin/admin-(ajax|post)\.php" \
    "chain,id:1002386,phase:2,deny,status:403,log,msg:'Block CVE-2025-23862 plugin action'"
SecRule ARGS:action "@rx contact-form-7-anti-spambot" \
    "chain"
SecRule &REQUEST_COOKIES:/wordpress_logged_in_/ "@eq 0"