Data Integration Hub 9.6.1 HotFix1 is a security fix. It introduces enhancements that tighten client and server security. Most of the enhancements are implemented on the server and have no impact on users. There are few enhancements that might affect system usage:

• User Name and Password Environment Variables in Command Line Utilities
• Restrict Remote Data Integration Hub Server Shutdown and Startup
• Protect Calls from PowerCenter Workflows to the Data Integration Hub Server with a Secret Token
• Secure Communications with PowerCenter Services.

You can download the Hotfix from here.

Informatica Data Integration Hub - 9.6.1HF1 - Release Notes - (English)