CVE-2025-46473: Social Counter Deserialization Vulnerability

CVE-2025-46473 Overview

CVE-2025-46473 is a PHP Object Injection vulnerability in the Prisna Social Counter WordPress plugin. The flaw stems from Deserialization of Untrusted Data [CWE-502] and affects all versions of the social-counter plugin up to and including 2.0.5. An authenticated attacker with high privileges can inject crafted serialized PHP objects that the plugin deserializes, leading to compromise of confidentiality, integrity, and availability on the host WordPress instance. The vulnerability was published to the National Vulnerability Database (NVD) on April 24, 2025, with a CVSS 3.1 base score of 7.2.

Critical Impact
Successful exploitation enables arbitrary PHP object instantiation, which can chain into remote code execution, data theft, or full site takeover when suitable gadget chains are present in the WordPress core, themes, or other installed plugins.

Affected Products

Prisna Social Counter (social-counter) WordPress plugin — all versions through 2.0.5
WordPress sites running the plugin alongside any code that exposes usable POP (Property-Oriented Programming) gadget chains
Hosting environments where the WordPress administrator account is shared or weakly protected

Discovery Timeline

2025-04-24 - CVE-2025-46473 published to NVD
2026-04-23 - Last updated in NVD database

Technical Details for CVE-2025-46473

Vulnerability Analysis

The Prisna Social Counter plugin passes attacker-controlled input to a PHP deserialization routine without validating the structure or origin of the serialized data. When PHP processes a serialized payload through unserialize(), it reconstructs objects and invokes magic methods such as __wakeup(), __destruct(), or __toString(). An attacker who can deliver a crafted serialized string to the vulnerable sink triggers these methods on classes already loaded in the WordPress runtime. If a usable gadget chain exists in the WordPress core, theme, or another plugin, the chain can be pivoted into file writes, SQL execution, or arbitrary code execution. The issue is classified as Insecure Deserialization leading to Object Injection.

Root Cause

The root cause is unsafe handling of serialized input within the plugin's request processing logic. The plugin treats the payload as trusted data and reconstructs PHP objects from it without using safe alternatives such as json_decode() or applying an allowed_classes allowlist. Versions through 2.0.5 lack the input validation needed to reject hostile serialized streams.

Attack Vector

Exploitation is performed over the network against the WordPress site. The CVSS vector indicates the attacker must hold high privileges on the target, meaning a privileged WordPress account or equivalent access is required. No user interaction is needed. Once the attacker submits a crafted serialized payload to the vulnerable endpoint, the plugin deserializes it and instantiates attacker-chosen classes. The vulnerability mechanism is documented in the Patchstack WordPress Plugin Vulnerability advisory. No verified proof-of-concept code is publicly available, and EPSS data places the probability of observed exploitation in the low range.

Detection Methods for CVE-2025-46473

Indicators of Compromise

Inbound HTTP requests to plugin endpoints containing serialized PHP markers such as O:, a:, or s: followed by class or property identifiers
Unexpected PHP errors referencing __wakeup, __destruct, or unserialize() in WordPress or PHP-FPM logs
New or modified PHP files under wp-content/plugins/social-counter/ or unexpected administrator accounts created shortly after suspicious requests
Outbound network connections initiated by the PHP worker process to unknown hosts following plugin activity

Detection Strategies

Inspect web server access logs for POST or GET parameters whose values match PHP serialization grammar targeting the social-counter plugin paths
Enable WordPress audit logging to capture privileged actions taken by accounts that interact with the plugin
Apply a Web Application Firewall (WAF) rule that flags serialized PHP payloads delivered to plugin endpoints
Correlate authentication events for high-privilege accounts with subsequent plugin requests to detect compromised administrator sessions

Monitoring Recommendations

Monitor file integrity on the wp-content/plugins/ and wp-content/uploads/ directories for unexpected writes
Alert on creation of WordPress users with administrator role or modifications to the wp_optionsactive_plugins value
Track PHP process activity for unusual child processes such as shells, curl, or wget originating from the web server user
Forward WordPress, PHP, and web server logs into a centralized analytics platform for correlation and retention

How to Mitigate CVE-2025-46473

Immediate Actions Required

Identify all WordPress instances running the Prisna Social Counter plugin at version 2.0.5 or earlier
Deactivate and remove the plugin if a patched version is not available or not strictly required
Rotate credentials for all WordPress administrator accounts and enforce multi-factor authentication
Audit the site for unauthorized administrator users, modified plugin files, and unknown scheduled tasks in wp-cron

Patch Information

At the time of NVD publication, no fixed version has been confirmed for the Prisna Social Counter plugin; versions through 2.0.5 are reported as affected. Administrators should consult the Patchstack advisory for the Social Counter plugin for the latest remediation status and apply any vendor update as soon as it becomes available.

Workarounds

Remove the social-counter plugin from active WordPress installations until a vendor patch is verified
Restrict access to /wp-admin/ and plugin endpoints using IP allowlists or HTTP authentication at the reverse proxy
Deploy WAF rules that block requests containing PHP serialization markers in parameters bound for the plugin
Apply least-privilege principles by limiting the number of accounts that hold the administrator role

bash

# Example: block PHP serialized payloads to the plugin path with an Nginx rule
location ~* /wp-content/plugins/social-counter/ {
    if ($args ~* "(^|&)[^=]+=O%3A[0-9]+%3A%22") { return 403; }
    if ($request_body ~* "O:[0-9]+:\"") { return 403; }
}