CVE-2024-34802: Wpfoxly Adfoxly Auth Bypass Vulnerability

CVE-2024-34802 Overview

CVE-2024-34802 is a Missing Authorization vulnerability (CWE-862) affecting the AdFoxly – Ad Manager, AdSense Ads & Ads.Txt WordPress plugin developed by WPFoxly. This broken access control flaw allows unauthenticated attackers to access restricted functionality without proper authorization checks, potentially leading to complete site compromise.

Critical Impact

This vulnerability enables unauthenticated attackers to bypass authorization controls, potentially allowing unauthorized access to administrative functions, data manipulation, and complete compromise of WordPress installations running the vulnerable plugin.

Affected Products

• AdFoxly – Ad Manager, AdSense Ads & Ads.Txt versions up to and including 1.8.5
• WordPress installations with the vulnerable AdFoxly plugin installed
• Sites utilizing AdFoxly for Google AdSense and ad management functionality

Discovery Timeline

• 2024-06-09 - CVE-2024-34802 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2024-34802

Vulnerability Analysis

This vulnerability stems from missing authorization checks within the AdFoxly WordPress plugin. The plugin fails to properly validate user permissions before allowing access to sensitive functionality, constituting a classic broken access control vulnerability. In WordPress environments, plugins are expected to implement capability checks using functions like current_user_can() to verify that the requesting user has appropriate privileges before executing sensitive operations.

When these authorization checks are absent, any user—including unauthenticated visitors—can invoke restricted functionality by directly accessing AJAX endpoints or form handlers that should be protected. This type of vulnerability is particularly dangerous in WordPress plugins that manage advertising configurations, as it could allow attackers to inject malicious advertisements, modify site monetization settings, or leverage the access to further compromise the WordPress installation.

Root Cause

The root cause of CVE-2024-34802 is the absence of proper authorization verification in the AdFoxly plugin codebase. WordPress plugins must explicitly implement permission checks on every sensitive action. When developers fail to include these checks—either by omission or by incorrect implementation—the plugin becomes vulnerable to unauthorized access. The vulnerability affects all versions from initial release through 1.8.5, indicating this was a fundamental design flaw rather than a regression.

Attack Vector

The attack vector is network-based, requiring no authentication and no user interaction. An attacker can exploit this vulnerability remotely by sending crafted HTTP requests directly to vulnerable endpoints exposed by the AdFoxly plugin. Since no privileges are required and the attack complexity is low, exploitation is straightforward once vulnerable endpoints are identified.

The attacker would typically enumerate WordPress AJAX actions or REST API endpoints registered by the plugin, then invoke these endpoints without authentication to perform unauthorized operations such as modifying ad configurations, accessing sensitive data, or potentially escalating to further attacks against the WordPress installation.

Detection Methods for CVE-2024-34802

Indicators of Compromise

• Unusual HTTP requests to WordPress AJAX endpoints (admin-ajax.php) with AdFoxly-related actions from unauthenticated sessions
• Unauthorized modifications to ad configurations or AdSense settings without administrator activity
• Unexpected changes to ads.txt file contents managed by the plugin
• Log entries showing access to AdFoxly plugin functionality from unknown or external IP addresses

Detection Strategies

• Monitor WordPress access logs for requests to admin-ajax.php containing AdFoxly-related action parameters from unauthenticated users
• Implement Web Application Firewall (WAF) rules to detect and block exploitation attempts targeting WordPress plugin endpoints
• Deploy file integrity monitoring to detect unauthorized changes to plugin configuration files
• Review WordPress audit logs for plugin setting modifications without corresponding admin sessions

Monitoring Recommendations

• Enable verbose logging for WordPress AJAX requests and analyze patterns for anomalous unauthenticated access
• Configure alerting for changes to advertising configuration files or database entries managed by AdFoxly
• Implement network-level monitoring for unusual traffic patterns to WordPress installations
• Regularly audit installed plugin versions against known vulnerability databases

How to Mitigate CVE-2024-34802

Immediate Actions Required

• Update AdFoxly plugin to a patched version beyond 1.8.5 immediately
• If no patch is available, deactivate and remove the AdFoxly plugin until a secure version is released
• Audit WordPress installation for signs of compromise including unauthorized configuration changes
• Review and restore any modified advertising configurations or ads.txt contents
• Implement WAF rules to block unauthenticated access to AdFoxly plugin endpoints as an interim measure

Patch Information

Organizations should check the WordPress plugin repository and the Patchstack Advisory on Adfoxly Vulnerability for the latest patch information. Ensure that WordPress auto-updates are enabled for plugins or establish a regular patching schedule to address vulnerabilities promptly.

Workarounds

• Disable the AdFoxly plugin entirely until a patched version is available
• Implement server-level access controls to restrict access to WordPress AJAX endpoints from untrusted sources
• Deploy a WAF with rules specifically targeting unauthorized access to plugin functionality
• Use WordPress security plugins to add additional authorization layers on AJAX actions

# Disable AdFoxly plugin via WP-CLI
wp plugin deactivate adfoxly --path=/var/www/html/wordpress

# Verify plugin is disabled
wp plugin list --path=/var/www/html/wordpress | grep adfoxly

# Check for available updates
wp plugin update --all --dry-run --path=/var/www/html/wordpress