Description

Deserialization of Untrusted Data vulnerability in ThemeREX Group Dwell dwell allows Object Injection.This issue affects Dwell: from n/a through 1.16.0.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "9.8",
  "pubDate": "2026-10-10T08:17:06.683Z",
  "pubdate": "2026-10-10T08:17:06.683Z",
  "executiveSummary": "The Dwell theme developed by ThemeREX contains a critical deserialization vulnerability originating from the processing of untrusted user-supplied data. This flaw permits an Object Injection attack, potentially leading to unauthorized code execution, data manipulation, or denial of service.\nThe vulnerability affects all versions of the Dwell theme from its initial release through version 1.16.0. By injecting malicious serialized objects into the application, an unauthenticated or low-privileged attacker can manipulate the internal state of the application or trigger unintended PHP object behavior.\nSuccessful exploitation poses a severe risk to the confidentiality, integrity, and availability of the host WordPress installation. Because deserialization often facilitates Property-Oriented Programming (POP) chains, an attacker may leverage existing theme or plugin code to achieve Remote Code Execution (RCE). Organizations utilizing the affected version should treat this as a high-priority security issue, as the attack vector does not necessarily require deep prior knowledge of the target system beyond the existence of vulnerable endpoints that handle serialized input.",
  "technicalDetails": "The vulnerability is rooted in the insecure implementation of PHP's unserialize() function within the Dwell theme codebase. When the theme processes user-provided data via specific parameters—typically retrieved from HTTP requests (GET/POST) or cookies—it fails to perform adequate validation or sanitization before passing the input to a deserialization routine.\nObject Injection occurs when an application deserializes untrusted data that has been modified to contain serialized representations of arbitrary classes available in the environment. In the context of the Dwell theme, the application expects serialized data to reconstitute legitimate objects; however, an attacker can craft a payload containing a serialized object of a different, pre-existing class. During the execution of unserialize(), PHP automatically triggers magic methods—such as __wakeup(), __destruct(), or __toString()—upon the instantiation of these objects.\nThe attack flow follows a structured methodology: First, the attacker identifies an entry point where the theme consumes serialized data. Second, the attacker performs reconnaissance to identify available PHP classes (POP gadgets) within the theme's core files, WordPress core, or other installed plugins that perform dangerous operations (e.g., file system manipulation, database queries, or command execution) within their magic methods. Third, the attacker constructs a malicious payload containing a serialized object specifically designed to chain these gadgets together. Finally, the attacker submits this payload to the vulnerable endpoint.\nUpon processing the payload, the application instantiates the attacker-controlled class, triggering the gadget chain. If the chain is successful, the attacker can influence the application logic, overwrite sensitive properties, or execute arbitrary system-level commands with the privileges of the web server process. The vulnerability is particularly dangerous because the exploitation is independent of the specific application logic, relying instead on the inherent dangers of the PHP serialization mechanism when applied to untrusted sources. The lack of integrity checks (such as digital signatures or HMACs) on the serialized data allows the payload to be interpreted as legitimate by the backend component, leading to complete compromise of the affected site's internal data structures."
}