The customer will be able to download the Hotfix from the TIBCO Support Customer Portal Web UI using their username and password for the TIBCO Support Web page.Once logged on they can find the Hotfix under the Download Menu :

AvailableDownloads/TRA_Designer/5.9.1/hotfix-06

OR

The customer will be able to download the Hotfix by using direct link to TRA_Designer/5.9.1/hotfix-06
https://support.tibco.com/s/hotfixes?id=a011a000009RwqMAAS
 

OR

Refer to  Article 000022290 : How can TIBCO customers download / access all GA hotfixes
Link to Article  000022290 :https://support.tibco.com/s/article/hotfix

Please contact TIBCO Support if you have any problems finding or downloading this hotfix.
Listed below is a summary of updates included. Refer to the associated readme document for any additional information.

================================================================================
Closed Issues in 5.9.1_HF-006 (This Release)

TRA-4096
To fix security vulnerabilities, the version of Tomcat that is bundled with TRA 
has been upgraded to Tomcat 7.0.82.

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Install the Hotfix by using direct link to TRA_Designer/5.9.1/hotfix-06
https://support.tibco.com/s/hotfixes?id=a011a000009RwqMAAS