CVE-2026-39691: Crypto Donation Box Auth Bypass Flaw

CVE-2026-39691 Overview

A Missing Authorization vulnerability has been identified in the AdAstraCrypto Cryptocurrency Donation Box – Bitcoin & Crypto Donations WordPress plugin. This vulnerability allows attackers to exploit incorrectly configured access control security levels, potentially enabling unauthorized access to plugin functionality and settings that should be restricted to authenticated administrators.

Critical Impact

Attackers can bypass access controls to perform unauthorized actions within the Cryptocurrency Donation Box plugin, potentially manipulating donation wallet addresses or accessing sensitive configuration data.

Affected Products

• Cryptocurrency Donation Box – Bitcoin & Crypto Donations plugin versions through 2.2.13
• WordPress installations running the vulnerable cryptocurrency-donation-box plugin

Discovery Timeline

• 2026-04-08 - CVE-2026-39691 published to NVD
• 2026-04-08 - Last updated in NVD database

Technical Details for CVE-2026-39691

Vulnerability Analysis

This vulnerability is classified as CWE-862 (Missing Authorization), which occurs when a software application does not perform authorization checks when an actor attempts to access a resource or perform an action. In the context of the Cryptocurrency Donation Box plugin, the missing authorization allows unauthenticated or low-privileged users to access functionality that should be restricted to administrators only.

The vulnerability exists because the plugin fails to properly verify user capabilities before executing sensitive operations. WordPress plugins typically rely on capability checks using functions like current_user_can() to verify that the requesting user has appropriate permissions. When these checks are absent or improperly implemented, attackers can directly invoke AJAX handlers or access administrative endpoints without proper authentication.

Root Cause

The root cause of this vulnerability is the absence of proper authorization checks in the plugin's code paths. The cryptocurrency-donation-box plugin exposes certain functionality through WordPress hooks (likely AJAX actions or REST endpoints) without validating that the requesting user has the necessary administrative capabilities. This represents a fundamental access control design flaw where security checks were either never implemented or were incorrectly configured.

Attack Vector

The attack vector for this vulnerability involves an attacker sending crafted requests to the plugin's exposed endpoints. Since the plugin fails to verify authorization, these requests are processed regardless of the user's authentication status or role. An attacker could potentially:

1. Access the plugin's administrative AJAX handlers directly by sending POST requests to admin-ajax.php with the appropriate action parameter
2. Modify donation wallet addresses to redirect cryptocurrency donations
3. Access or modify plugin configuration settings
4. Retrieve sensitive information stored by the plugin

The vulnerability can be exploited remotely through the WordPress installation's web interface without requiring prior authentication, depending on the specific functionality exposed.

Detection Methods for CVE-2026-39691

Indicators of Compromise

• Unexpected changes to cryptocurrency wallet addresses configured in the donation plugin
• Unusual AJAX requests to WordPress admin-ajax.php targeting cryptocurrency-donation-box actions from unauthenticated sessions
• Access logs showing requests to plugin-specific endpoints from unknown or suspicious IP addresses
• Unauthorized modifications to plugin settings without corresponding admin user activity

Detection Strategies

• Monitor WordPress database for unauthorized changes to plugin options with the cryptocurrency_donation_box prefix
• Implement Web Application Firewall (WAF) rules to detect and block unauthorized access attempts to plugin AJAX handlers
• Review access logs for patterns of requests targeting the vulnerable plugin endpoints without valid authentication cookies
• Deploy file integrity monitoring to detect any unauthorized modifications to plugin files

Monitoring Recommendations

• Enable detailed logging for WordPress AJAX requests and filter for cryptocurrency-donation-box related actions
• Set up alerts for changes to cryptocurrency wallet configuration options in the WordPress options table
• Monitor for new or modified scheduled tasks that could indicate persistent access attempts
• Implement SentinelOne endpoint protection to detect and respond to suspicious web server activity patterns

How to Mitigate CVE-2026-39691

Immediate Actions Required

• Update the Cryptocurrency Donation Box plugin to a patched version immediately when available from the vendor
• Temporarily deactivate the cryptocurrency-donation-box plugin if it is not critical to site operations until a patch is released
• Audit current plugin configuration to verify that wallet addresses and settings have not been tampered with
• Review WordPress user accounts for any unauthorized additions or privilege escalations

Patch Information

The vulnerability affects Cryptocurrency Donation Box – Bitcoin & Crypto Donations plugin versions through 2.2.13. Check the Patchstack Vulnerability Report for the latest patch status and updated version information from the vendor. Users should update to a version higher than 2.2.13 once a security fix is released.

Workarounds

• Implement server-level access controls to restrict access to admin-ajax.php for specific plugin actions from unauthenticated users
• Use a WordPress security plugin to add additional authorization layers for AJAX requests
• Configure a Web Application Firewall (WAF) to block suspicious requests targeting the vulnerable plugin endpoints
• Consider using WordPress capability management plugins to enforce stricter role-based access control

# Example: Block unauthorized AJAX requests via .htaccess (Apache)
# Add to WordPress .htaccess file to restrict admin-ajax.php access
<Files admin-ajax.php>
    <RequireAll>
        Require all granted
    </RequireAll>
</Files>
# Note: This is a general hardening measure; specific action blocking 
# requires custom WAF rules based on the plugin's AJAX action names