CVE-2026-24385: Podlove Web Player Deserialization Flaw

CVE-2026-24385 Overview

CVE-2026-24385 is a Deserialization of Untrusted Data vulnerability (CWE-502) affecting the Podlove Web Player WordPress plugin developed by gerritvanaaken. This vulnerability allows attackers to perform PHP Object Injection attacks against vulnerable WordPress installations running the affected plugin versions.

PHP Object Injection vulnerabilities occur when user-supplied input is unsafely passed to PHP's unserialize() function, allowing attackers to instantiate arbitrary objects and potentially chain them to achieve malicious outcomes such as remote code execution, file manipulation, or sensitive data disclosure.

Critical Impact

Successful exploitation of this PHP Object Injection vulnerability could allow attackers to execute arbitrary code, manipulate files, or compromise the integrity of affected WordPress installations running Podlove Web Player version 5.9.1 or earlier.

Affected Products

• Podlove Web Player WordPress Plugin version 5.9.1 and earlier
• WordPress installations utilizing the podlove-web-player plugin

Discovery Timeline

• 2026-03-05 - CVE-2026-24385 published to NVD
• 2026-03-05 - Last updated in NVD database

Technical Details for CVE-2026-24385

Vulnerability Analysis

This vulnerability exists in the Podlove Web Player WordPress plugin, a popular solution for embedding podcast players on WordPress websites. The core issue stems from improper handling of serialized PHP data, where user-controllable input is passed to deserialization functions without adequate validation or sanitization.

When exploited, attackers can inject malicious serialized objects that, upon deserialization, trigger dangerous operations through PHP's magic methods such as __wakeup(), __destruct(), or __toString(). The impact depends on the availability of exploitable class chains (gadgets) within the WordPress installation and its plugins.

Root Cause

The root cause of CVE-2026-24385 is the unsafe deserialization of untrusted data within the Podlove Web Player plugin. The vulnerability arises when the application processes serialized PHP objects from user input without proper validation, allowing attackers to control the type and properties of instantiated objects.

PHP's native unserialize() function is inherently dangerous when used with untrusted input, as it can instantiate any available class and populate its properties with attacker-controlled values. This violates the principle of never trusting user-supplied input for security-critical operations.

Attack Vector

The attack vector for this vulnerability involves submitting crafted serialized PHP payloads to the vulnerable plugin functionality. Attackers construct a malicious serialized string containing objects that, when deserialized, execute unintended operations through their magic methods.

The exploitation process typically follows this pattern: the attacker identifies the vulnerable deserialization point, discovers available gadget chains within the WordPress ecosystem, constructs a serialized payload that leverages these gadgets, and submits the payload to trigger the vulnerability. The deserialization of this malicious payload can result in arbitrary code execution, file system manipulation, or other security-impacting actions depending on available class definitions.

For detailed technical information about this vulnerability, refer to the Patchstack Vulnerability Report.

Detection Methods for CVE-2026-24385

Indicators of Compromise

• Unusual serialized data patterns in web server access logs, particularly containing PHP object notation (O:, a:, s:)
• Unexpected file modifications or new files created in WordPress directories
• Anomalous PHP process behavior or execution of unexpected system commands
• Evidence of reconnaissance activity targeting the Podlove Web Player plugin endpoints

Detection Strategies

• Implement Web Application Firewall (WAF) rules to detect and block serialized PHP object patterns in HTTP requests
• Monitor WordPress plugin directories for unauthorized file changes or new file creation
• Review web server logs for requests containing suspicious serialized object payloads
• Deploy endpoint detection solutions to identify malicious PHP execution patterns

Monitoring Recommendations

• Enable detailed logging for WordPress and the Podlove Web Player plugin to capture all incoming requests
• Configure file integrity monitoring on WordPress installation directories
• Establish baseline behavior monitoring for PHP processes on WordPress hosting servers
• Implement alerting for any attempts to access plugin files with unusual parameters

How to Mitigate CVE-2026-24385

Immediate Actions Required

• Audit your WordPress installations for the presence of Podlove Web Player plugin version 5.9.1 or earlier
• Monitor the plugin developer and WordPress plugin repository for security updates
• Implement WAF rules to filter serialized PHP object patterns in incoming requests
• Consider temporarily disabling the Podlove Web Player plugin until a patch is available

Patch Information

At the time of publication, organizations should monitor the official WordPress plugin repository and the Patchstack Vulnerability Report for updates regarding security patches for CVE-2026-24385. Update to a patched version as soon as one becomes available.

Workarounds

• Deploy a Web Application Firewall with rules to block requests containing serialized PHP objects
• Implement input validation at the application level to reject unexpected serialized data
• Consider using WordPress security plugins that provide virtual patching capabilities
• Temporarily deactivate the Podlove Web Player plugin if the functionality is not critical

# Configuration example - WordPress security hardening
# Add to wp-config.php to disable file editing
define('DISALLOW_FILE_EDIT', true);

# Enable WordPress debug logging (for monitoring purposes)
define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);
define('WP_DEBUG_DISPLAY', false);