CVE-2026-18391

CRITICAL CVSS 3.1: 9.8 EPSS 0.57%
Updated Aug 12, 2026
WordPress
Parameter Value
CVSS 9.8 (CRITICAL)
Affected Versions before 9.1.0
Type CWE-434 (Unrestricted File Upload)
Vendor WordPress
Public PoC No

The WooCommerce Subscriptions WordPress plugin before 9.1.0 does not validate user input before unserializing it on stores with High-Performance Order Storage enabled, leading to a PHP Object Injection issue which unauthenticated users can escalate to Remote Code Execution via a gadget chain present in the bundled dependencies.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed

Impact Assessment

Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service

CVSS Vector v3.1