IF you can get it, it appears the latest version for that hardware is is 6.4.4.25.
I would STRONGLY recommend you contact your Aruba account team to see how you can get moved to a secure wireless system. Controllers & APs that old have multiple unpatched vulnerabilities, exposing your business to possible legal issues.
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Bruce Osborne ACCP ACMP
Liberty University
The views expressed here are my personal views and not those of my employer
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