From GameWatcher: “Hitman 3 builds upon the foundation of the previous entries in the trilogy, which means that you’ll use some familiar tricks to get to your targets. The Dubai safe code is one such example, offering Agent 47 access to a hidden keycard in the location’s security rooms.
As you can probably expect, you don’t exactly waltz in knowing Hitman 3’s Dubai safe code. It’s locked away to keep it from getting in the hands of, say, skilled assassin’s looking to take out the people it’s supposed to protect. But that doesn’t mean it’s completely out of your reach.”
Source: N4G PC Hitman 3 Dubai Safe Code – How to Get the Keycard from the Security Room