Hyland OnBase versions prior to 17.0.2.87 (other versions may be affected) are vulnerable to unauthenticated remote code execution via insecure deserialization on the .NET Remoting TCP channel. The service registers a listener on port 6031 with the URI endpoint TimerServer, implemented in Hyland.Core.Timers.dll. This endpoint deserializes untrusted input using the .NET BinaryFormatter, allowing attackers to execute arbitrary code under the context of NT AUTHORITY\SYSTEM.