Description

Unauthenticated PHP Object Injection in Ultimate Maps by Supsystic < 1.5.0 versions.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "9.8",
  "pubDate": "2026-08-18T15:17:05.410Z",
  "pubdate": "2026-08-18T15:17:05.410Z",
  "executiveSummary": "An unauthenticated PHP Object Injection vulnerability has been identified in the Ultimate Maps by Supsystic plugin for WordPress in versions prior to 1.5.0.\nThe vulnerability allows remote, unauthenticated attackers to supply maliciously crafted serialized data to vulnerable endpoints handled by the plugin.\nSuccessful exploitation of this flaw can lead to severe security implications, potentially enabling attackers to achieve arbitrary code execution, conduct insecure deserialization attacks, perform server-side request forgery, or execute arbitrary file deletion depending on the gadget chains available within the application environment and PHP ecosystem.\nThe flaw stems from the insecure handling and unserialization of user-supplied input without proper validation or sanitization.\nAttackers do not require any prior authentication or privileged access to interact with the vulnerable parameter, exposing the affected WordPress installations to high-severity remote exploitation over the network.\nMitigation requires immediate administrative action to remediate the risk, primarily focusing on updating the affected plugin to version 1.5.0 or later where the insecure deserialization vector has been resolved by the vendor.",
  "technicalDetails": "The vulnerability resides in the Ultimate Maps by Supsystic plugin for WordPress, specifically affecting versions strictly less than 1.5.0.\nThe root cause of the vulnerability is the improper implementation of PHP's unserialize() function on untrusted data derived from HTTP requests without prior validation, type checking, or cryptographic signing.\nPHP Object Injection occurs when user-controllable input is passed directly to the unserialize() function in PHP, allowing an attacker to manipulate the internal state of the application and instantiate arbitrary PHP classes currently loaded into memory.\nBecause the application lacks authentication requirements and the vulnerable code path is exposed via network protocols, an unauthenticated remote attacker can issue crafted HTTP requests targeting the vulnerable endpoints.\nThe attack flow proceeds as follows: First, the attacker identifies the entry point accepting serialized payloads within the Ultimate Maps by Supsystic plugin. Second, the attacker crafts a malicious serialized string containing instantiated objects of specific classes available in the application or its dependencies, commonly referred to as POP (Property-Oriented Programming) gadget chains. Third, the crafted payload is transmitted via HTTP POST or GET parameters to the vulnerable script. Fourth, the application processes the input and passes it to the unserialize() function. Fifth, upon deserialization, PHP automatically invokes magic methods such as __wakeup() or __destruct() within the instantiated gadget classes, triggering the execution flow dictated by the attacker.\nDepending on the classes present in the WordPress core, active themes, and installed plugins, the post-exploitation impact can escalate from local file inclusion and arbitrary file deletion to remote code execution on the underlying web server hosting the vulnerable application.\nNetwork exposure is fully remote over HTTP/HTTPS, requiring no privileges or interaction from authenticated users or administrators."
}