CVE-2025-47553: DZS Video Gallery Object Injection Flaw

CVE-2025-47553 Overview

CVE-2025-47553 is a Deserialization of Untrusted Data vulnerability affecting the DZS Video Gallery WordPress plugin by Digital zoom studio. This vulnerability allows attackers to perform PHP Object Injection attacks against vulnerable WordPress installations running affected versions of the plugin. The vulnerability stems from improper handling of serialized data, enabling authenticated attackers with low privileges to inject malicious objects into the application.

Critical Impact

Authenticated attackers can exploit PHP Object Injection to potentially achieve remote code execution, data manipulation, or complete WordPress site compromise through chained gadgets in the plugin or other installed components.

Affected Products

• DZS Video Gallery WordPress plugin versions through 12.25
• WordPress installations running vulnerable DZS Video Gallery versions
• Sites utilizing the dzs-videogallery plugin for video content management

Discovery Timeline

• 2026-01-06 - CVE CVE-2025-47553 published to NVD
• 2026-01-08 - Last updated in NVD database

Technical Details for CVE-2025-47553

Vulnerability Analysis

This vulnerability is classified as CWE-502 (Deserialization of Untrusted Data), a category of flaws that occurs when an application deserializes data from untrusted sources without proper validation. In the context of PHP applications like WordPress plugins, this manifests as PHP Object Injection, where attackers can pass specially crafted serialized PHP objects to the application.

When the DZS Video Gallery plugin processes user-supplied serialized data through PHP's unserialize() function, an attacker can inject arbitrary PHP objects. If compatible "gadget chains" exist within the plugin, WordPress core, or other installed plugins, these injected objects can trigger dangerous operations during their instantiation or destruction phases through magic methods like __wakeup(), __destruct(), or __toString().

The vulnerability requires low-privilege authentication (such as a subscriber or contributor role) to exploit, but once access is obtained, the attack can be conducted over the network without user interaction.

Root Cause

The root cause of CVE-2025-47553 lies in the insecure deserialization of user-controlled input within the DZS Video Gallery plugin. The plugin fails to properly validate or sanitize serialized data before passing it to PHP's unserialize() function. This architectural flaw allows attackers to control the type and properties of objects being instantiated during the deserialization process.

Secure implementations should either avoid deserializing untrusted data entirely, use safer data formats like JSON, or implement strict allowlists for permitted object types when deserialization is necessary.

Attack Vector

The attack vector for this vulnerability is network-based, requiring an authenticated user with low privileges to submit malicious serialized data to the vulnerable plugin endpoint. The exploitation process involves:

1. An attacker authenticates to WordPress with minimal privileges (e.g., subscriber role)
2. The attacker identifies the vulnerable deserialization endpoint within the DZS Video Gallery plugin
3. The attacker crafts a malicious serialized PHP object containing a payload designed to trigger dangerous operations
4. Upon deserialization, the malicious object's magic methods execute, potentially leading to code execution, file operations, or database manipulation

The exploitation of PHP Object Injection vulnerabilities depends heavily on the availability of suitable gadget chains within the application's codebase. Common exploitation outcomes include arbitrary file deletion, remote code execution through write operations, and SQL injection through database-related gadgets.

Detection Methods for CVE-2025-47553

Indicators of Compromise

• Unusual serialized data patterns in HTTP POST requests targeting DZS Video Gallery plugin endpoints
• Presence of suspicious PHP object signatures (e.g., O: prefixed strings with unexpected class names) in request logs
• Unexpected file system modifications or new files appearing in WordPress directories
• Anomalous database queries or modifications originating from plugin contexts

Detection Strategies

• Monitor web application firewall (WAF) logs for serialized PHP object patterns in request parameters
• Implement input validation rules to detect and block serialized data containing object markers
• Deploy runtime application self-protection (RASP) solutions to detect deserialization attacks
• Review WordPress access logs for repeated requests to DZS Video Gallery plugin endpoints with large or unusual payloads

Monitoring Recommendations

• Enable detailed logging for the DZS Video Gallery plugin and WordPress core
• Implement file integrity monitoring on WordPress installations to detect unauthorized changes
• Configure security plugins to alert on suspicious authentication patterns or privilege escalation attempts
• Monitor for PHP error logs indicating failed object instantiation or method calls on unexpected classes

How to Mitigate CVE-2025-47553

Immediate Actions Required

• Update DZS Video Gallery plugin to a patched version immediately when available
• Review WordPress user accounts and remove unnecessary low-privilege accounts
• Implement a web application firewall with rules to block serialized PHP object injection attempts
• Audit installed plugins and themes for compatible gadget chains that could increase exploitation impact

Patch Information

Organizations should monitor the Patchstack WordPress Vulnerability Database for updated patch information and remediation guidance. Until a patch is available, implement the workarounds listed below to reduce exposure.

Workarounds

• Temporarily disable the DZS Video Gallery plugin until a security update is released
• Restrict WordPress user registration to prevent attackers from obtaining authenticated access
• Implement IP-based access controls to limit administrative and authenticated access to trusted networks
• Deploy virtual patching through a WAF to filter malicious serialized payloads targeting the vulnerable endpoint

# Example WAF rule to block serialized PHP object patterns
# Add to .htaccess or WAF configuration
# Block requests containing serialized object patterns
RewriteEngine On
RewriteCond %{QUERY_STRING} (^|&).*O:[0-9]+: [NC,OR]
RewriteCond %{REQUEST_BODY} O:[0-9]+: [NC]
RewriteRule .* - [F,L]