Description

Deserialization of Untrusted Data vulnerability in Vektor Inc. VK Google Job Posting Manager vk-google-job-posting-manager allows Object Injection.This issue affects VK Google Job Posting Manager: from n/a through 1.3.1.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.8",
  "pubDate": "2026-10-05T20:17:07.177Z",
  "pubdate": "2026-10-05T20:17:07.177Z",
  "executiveSummary": "The VK Google Job Posting Manager plugin, developed by Vektor Inc., is susceptible to a Deserialization of Untrusted Data vulnerability, categorized as an Object Injection flaw.\nThis vulnerability exists within versions ranging from n/a through 1.3.1.\nThe flaw arises when the application processes user-supplied serialized data without adequate validation or sanitization, allowing an attacker to instantiate arbitrary PHP objects.\nSuccessful exploitation permits an attacker to perform unauthorized operations, which may include remote code execution, file system manipulation, or denial-of-service, depending on the available gadget chains present in the application's environment.\nThis represents a critical security risk, as the exploitation of deserialization vulnerabilities can lead to full site compromise if vulnerable classes (gadgets) are present in the underlying PHP codebase or third-party plugins.\nAttackers can leverage this vulnerability without specific authentication in many scenarios, depending on the exposure of the vulnerable endpoint, posing a significant threat to the confidentiality, integrity, and availability of the affected WordPress instance.",
  "technicalDetails": "The vulnerability is rooted in the insecure use of PHP's unserialize() function on untrusted input provided by the user. When an application deserializes data from an external source without first verifying the structure or content, it allows the object instantiation process to be manipulated.\nIn the context of VK Google Job Posting Manager, the plugin fails to implement sufficient integrity checks or type validation before passing user-controlled data to the deserialization routine. PHP's serialization mechanism allows for the definition of object properties within the serialized string; by crafting a malicious payload, an attacker can influence the state of objects or instantiate classes that were not intended by the developer.\nThe attack flow typically follows these steps: First, the attacker identifies an entry point within the plugin that accepts serialized data via HTTP requests (such as GET or POST parameters or cookies). Second, the attacker constructs a malicious payload—often leveraging known gadget chains—which are sequences of existing code within the application that, when executed during the object's wakeup or destruction phase, perform unintended actions. Third, the attacker transmits this serialized object to the vulnerable endpoint. Upon processing, the server unserializes the input, triggering the magic methods (e.g., __destruct(), __wakeup(), or __toString()) associated with the injected object.\nIf the application environment contains 'gadget' classes—typically classes that implement these magic methods and perform dangerous actions such as file operations, database queries, or command execution—the attacker can chain these behaviors to achieve remote code execution (RCE). Because the plugin lacks validation, the scope of the exploit is constrained only by the available codebase's reachability and the server's permission level. The impact is significant, as it effectively elevates the attacker's ability to manipulate internal logic, bypass access controls, or extract sensitive system information. Post-exploitation impact may involve complete site takeover, persistent backdoor installation, or the exfiltration of sensitive configuration data stored in the WordPress database or environment variables.\nThis vulnerability highlights a critical breakdown in data handling practices, specifically where input trust boundaries are ignored during the reconstruction of complex data types, turning a standard data-processing function into an arbitrary execution primitive."
}