This vulnerability (CWE-639) in Sparx Systems Pro Cloud Server arises from improper authorization checks tied to user-controlled keys in the request. Specifically, the server relies on the requested URL for authentication, but an attacker can bypass this by omitting the "model" query parameter and embedding the model name in a binary blob in a POST request. This bypass allows unauthorized SQL query execution. Versions 6.1 (build 167) and earlier have been confirmed vulnerable; other versions have not been tested. No official remediation or patch has been disclosed by the vendor.

Successful exploitation allows an unauthenticated attacker to execute SQL queries on the server, bypassing authentication controls. This can lead to unauthorized data access or manipulation, representing a critical security risk. The CVSS 4.0 base score is 9.3, reflecting high impact and ease of exploitation without privileges or user interaction.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official fix or mitigation has been provided by Sparx Systems, users should consider restricting access to the Pro Cloud Server to trusted networks and monitor for unusual POST requests that omit the "model" parameter. Await vendor updates for an official patch or guidance.