CVE-2026-42718 in Booster for WooCommerce Plugin
Summary
by MITRE • 10/10/2026
Unauthenticated PHP Object Injection in Booster for WooCommerce <= 8.4.0 versions.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 10/10/2026
The vulnerability identified as an unauthenticated PHP object injection flaw within the Booster for WooCommerce plugin, affecting versions up to and including 8.4.0, represents a critical security risk that allows attackers to execute arbitrary code on vulnerable web servers without requiring valid user credentials. This type of vulnerability stems from the improper handling of serialized data inputs where the application fails to validate or sanitize objects before passing them to PHP's unserialize function. In modern WordPress ecosystems, this is particularly dangerous because it bypasses standard authentication mechanisms, enabling any internet-facing visitor with network access to exploit the flaw directly through HTTP requests. The core technical issue lies in the lack of strict type checking and whitelisting for deserialized data, which violates fundamental secure coding practices outlined under CWE-502, specifically Deserialization of Untrusted Data.
From a technical perspective, PHP object injection exploits the magic methods inherent to PHP classes, such as __wakeup(), __destruct(), or __toString(). When an attacker provides a crafted serialized string containing references to specific objects within the WordPress environment or loaded plugins, they can trigger these special functions during the deserialization process. This mechanism allows for remote code execution if dangerous class methods are available in the global scope of the application. The absence of authentication means that this attack vector is widely accessible, significantly lowering the barrier to entry for malicious actors compared to authenticated injection flaws which require compromised user accounts or privilege escalation steps first.
The operational impact of successfully exploiting this vulnerability can be severe and multifaceted. Attackers typically leverage PHP object injection to achieve Remote Code Execution (RCE), granting them full control over the underlying server environment hosting the WordPress instance. This level of access allows for the exfiltration of sensitive customer data, including credit card information stored in WooCommerce databases, which constitutes a direct violation of PCI DSS compliance requirements. Furthermore, compromised sites are frequently repurposed as nodes in botnets, used to launch distributed denial-of-service attacks against other targets, or utilized to distribute malware and phishing content to unsuspecting visitors. The persistence established through such an injection can lead to long-term unauthorized access even after the initial vulnerability is patched if backdoors are planted via file system modifications enabled by the RCE capability.
Mitigation strategies must prioritize immediate remediation alongside defensive hardening measures. The most effective solution is to upgrade the Booster for WooCommerce plugin to a version greater than 8.4.0, where developers have presumably implemented proper input validation and restricted deserialization to trusted sources only. For organizations unable to update immediately due to compatibility constraints, temporary mitigations include implementing Web Application Firewall rules that detect patterns associated with PHP serialization payloads in HTTP request parameters. Additionally, disabling the unserialize function entirely via server-level configuration or using a strict allowlist approach for any necessary object instantiation can significantly reduce the attack surface. Regular security audits and adherence to OWASP Top 10 guidelines regarding insecure deserialization are essential to prevent recurrence of such vulnerabilities in future development cycles.