A vulnerability in RDPngFileUpload.dll, as used in the IRM Next Generation booking system, allows a remote attacker to upload arbitrary content (such as a web shell component) to the SQL database and execute it with SYSTEM privileges. This vulnerability requires authentication to be exploited but can be paired with another vulnerability in the platform (CVE-2023-39420, which grants access to hardcoded credentials) to carry the attack without having assigned credentials. 

The RDPData.dll file exposes the /irmdata/api/common endpoint that handles session IDs,  among other features. By using a UNION SQL operator, an attacker can leak the sessions table, obtain the currently valid sessions and impersonate a currently logged-in user.

The /irmdata/api/ endpoints exposed by the IRM Next Generation booking engine authenticates requests using HMAC tokens. These tokens are however exposed in a JavaScript file loaded on the client side, thus rendering this extra safety mechanism useless.

The RDPWin.dll component as used in the IRM Next Generation booking engine includes a set of hardcoded API keys for third-party services such as Twilio and Vonage. These keys allow unrestricted interaction with these services.

The RDPCore.dll component as used in the IRM Next Generation booking engine, allows a remote user to connect to customers with an "admin" account and a corresponding password computed daily by a routine inside the DLL file. Once reverse-engineered, this routine can help an attacker generate the daily password and connect to application customers. Given that this is an administrative account, anyone logging into a customer deployment has full, unrestricted access to the application.