CVE-2025-49890: Organic Beauty Object Injection Vulnerability

CVE-2025-49890 Overview

CVE-2025-49890 is a PHP Object Injection vulnerability in the ThemeREX Organic Beauty WordPress theme. The flaw stems from deserialization of untrusted data [CWE-502] and affects all versions of the organic-beauty theme through 1.4.6. Unauthenticated attackers can send crafted serialized payloads over the network to trigger object injection during unserialize() processing. When combined with a suitable PHP object gadget chain present in WordPress core, plugins, or other themes, this can lead to remote code execution, arbitrary file operations, or full site compromise.

Critical Impact
Unauthenticated remote attackers can inject arbitrary PHP objects into the application, potentially leading to code execution and complete WordPress site takeover.

Affected Products

ThemeREX Organic Beauty WordPress theme (organic-beauty)
All versions from initial release through 1.4.6
WordPress installations using the vulnerable theme in any active configuration

Discovery Timeline

2025-08-20 - CVE-2025-49890 published to the National Vulnerability Database
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-49890

Vulnerability Analysis

The Organic Beauty theme processes attacker-controllable input through PHP's unserialize() function without validating the source or structure of the serialized data. PHP object injection occurs when untrusted serialized strings are converted back into live PHP objects. During instantiation, PHP invokes magic methods such as __wakeup(), __destruct(), and __toString() on the resulting objects. Attackers exploit these method invocations by chaining classes already loaded in the WordPress runtime into a POP (Property-Oriented Programming) gadget chain. The result can include arbitrary file writes, SQL injection, or command execution depending on the gadgets available in the target environment.

Root Cause

The root cause is unsafe deserialization of user-controllable data. The theme accepts serialized input from a request parameter, cookie, or option value and passes it directly to unserialize() without integrity checks, type restrictions, or use of safer alternatives such as json_decode(). This pattern maps directly to CWE-502.

Attack Vector

The attack vector is network-based and requires no authentication or user interaction. An attacker crafts a serialized PHP payload referencing a gadget chain and delivers it to the vulnerable endpoint exposed by the theme. When the theme deserializes the payload, magic methods on the injected objects execute automatically. Successful exploitation grants full impact on confidentiality, integrity, and availability of the WordPress instance.

The vulnerability manifests during PHP deserialization of externally supplied input. See the Patchstack Vulnerability Report for further technical context.

Detection Methods for CVE-2025-49890

Indicators of Compromise

Inbound HTTP requests containing serialized PHP patterns such as O:, a:, or s: in query strings, POST bodies, or cookies targeting theme endpoints
Unexpected PHP files, webshells, or modified theme files under wp-content/themes/organic-beauty/
New administrator accounts, unexpected scheduled tasks in wp_options (cron), or unknown plugins appearing after suspicious traffic
Outbound connections from the web server process to unfamiliar hosts following requests to Organic Beauty theme URLs

Detection Strategies

Inspect web server and WAF logs for serialized object markers targeting theme paths and reject or alert on matches
Monitor PHP error logs for __wakeup, __destruct, or class instantiation warnings tied to unexpected classes
Compare theme file hashes against a known-good baseline to detect tampering of organic-beauty files

Monitoring Recommendations

Enable file integrity monitoring across wp-content/ and alert on new or modified PHP files
Forward WordPress access logs, PHP-FPM logs, and WAF telemetry to a centralized data lake for correlation and long-term retention
Alert on privilege changes in wp_users and wp_usermeta, especially new users with administrator capabilities

How to Mitigate CVE-2025-49890

Immediate Actions Required

Deactivate the Organic Beauty theme on any site running version 1.4.6 or earlier until a patched release is confirmed and applied
Restrict access to the WordPress site with a WAF rule blocking serialized PHP payloads in request parameters and cookies
Rotate WordPress secret keys in wp-config.php, database credentials, and all administrator passwords if exploitation is suspected
Audit wp-content/ for unauthorized files and review recently created users and scheduled cron entries

Patch Information

At the time of publication, the vendor advisory listed on Patchstack indicates the vulnerability affects Organic Beauty through 1.4.6 with no fixed version specified. Administrators should consult the Patchstack Vulnerability Report for updated patch availability and switch to a maintained theme if no fix is released.

Workarounds

Replace the Organic Beauty theme with a maintained alternative that does not rely on unserialize() for untrusted input
Deploy a virtual patch through a WAF that blocks HTTP requests containing PHP serialization signatures such as O:\d+:" or a:\d+:{
Harden PHP by disabling dangerous functions where feasible and ensuring the web server runs with least-privileged filesystem permissions

bash

# Example ModSecurity rule to block serialized PHP object payloads
SecRule ARGS|ARGS_NAMES|REQUEST_COOKIES|REQUEST_BODY "@rx (?i)(O|C):[0-9]+:\"[a-zA-Z_\\x7f-\\xff][a-zA-Z0-9_\\x7f-\\xff]*\":[0-9]+:\{" \
    "id:1004990,phase:2,deny,status:403,log,msg:'Possible PHP Object Injection - CVE-2025-49890'"