CVE-2026-74012 in TaxoPress Plugin
Summary
by MITRE • 08/18/2026
Editor PHP Object Injection in TaxoPress <= 3.51.0 versions.
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Analysis
by VulDB Data Team • 08/19/2026
The vulnerability identified as an Editor PHP Object Injection within TaxoPress versions prior to or equal to 3.51.0 represents a critical security flaw rooted in the improper handling of serialized data during the plugin's editor functionality. This issue arises from the application's failure to adequately validate and sanitize user-supplied input before it is passed through PHP’s unserialize function, which is commonly used for deserializing objects stored in databases or configuration files. In modern web applications utilizing object-oriented programming paradigms, this specific weakness allows an attacker to craft a maliciously constructed serialized string that, when processed by the vulnerable application, results in the instantiation of arbitrary PHP objects with controlled properties and methods. This class of vulnerability is formally categorized under CWE-502, which denotes Deserialization of Untrusted Data, and it exploits the inherent risks associated with allowing external input to dictate object construction without sufficient integrity checks or type constraints.
From a technical perspective, the exploitation mechanism relies on the presence of PHP magic methods such as __wakeup, __destruct, or __toString within classes loaded by the TaxoPress plugin or its dependencies. When an attacker submits a crafted payload via the editor interface, typically through parameters that control taxonomy settings or custom field configurations, the application processes this input and attempts to deserialize it into a usable format for display or storage. Because the validation logic is insufficient, the PHP engine executes the magic methods associated with the injected object class rather than treating the data as simple text or safe structured information. This execution context often runs with the same privileges as the web server process, granting the attacker significant control over the application's runtime environment. The flaw is particularly dangerous because it does not require complex network-level interactions; instead, it can be triggered through standard HTTP requests that interact with the plugin’s administrative interface or public-facing taxonomy displays if input sanitization is also lacking in those areas.
The operational impact of this vulnerability extends far beyond simple data leakage or defacement. Successful exploitation enables Remote Code Execution (RCE), allowing an attacker to execute arbitrary system commands on the underlying server hosting the WordPress instance. This can lead to complete compromise of the web application, including access to sensitive database credentials, user session tokens, and other configuration files that reside in accessible directories. Furthermore, because TaxoPress is a widely used plugin for managing taxonomies such as categories and tags, an exploit could be chained with other vulnerabilities or used to establish persistent backdoors within the WordPress installation. The attacker may leverage this access to pivot into internal network segments if the web server has broader connectivity than intended, thereby escalating the scope of the breach from a single application compromise to a potential infrastructure-wide incident. This aligns with ATT&CK technique T1059, Command and Scripting Interpreter, as well as T1203, Exploitation for Client Execution or System Access depending on the specific payload delivered through the deserialization chain.
Mitigation strategies must address both immediate remediation and long-term architectural improvements. The primary and most effective solution is to upgrade TaxoPress to version 3.51.1 or later, where developers have implemented stricter input validation and replaced unsafe deserialization practices with safer alternatives such as JSON decoding for structured data that does not require object instantiation. For environments where immediate upgrading is not feasible due to compatibility constraints, administrators should restrict access to the plugin’s editor interfaces by enforcing strong authentication mechanisms and limiting administrative privileges to trusted IP addresses or specific user roles. Additionally, implementing a Web Application Firewall (WAF) with rulesets designed to detect patterns associated with PHP object injection payloads can provide an additional layer of defense by blocking malicious serialized strings before they reach the application logic. It is also advisable to audit custom code within themes and other plugins for similar deserialization vulnerabilities, as this flaw often indicates broader weaknesses in how third-party extensions handle user input. Regular security audits and adherence to secure coding standards that prohibit direct use of unserialize on untrusted data are essential practices to prevent recurrence of such critical flaws in WordPress ecosystems.