Installing Software and Keeping It Updated

Sam finds a free "PDF converter" through a pop-up advert and wants to install it on the till PC. Every program you install runs with your permissions and can see your files. Choosing what goes on a machine, and keeping it up to date, is one of the cheapest defences there is.

The rule

Install from the real source, only what you need, and keep it updated.

Three habits, each closing a different door:

• The real source. Get software from the official vendor site or the OS's official store or package manager. Fake download sites and "cracked" paid software are a classic way malware arrives.
• Only what you need. Every extra program is extra code that can have flaws. If the shop does not use a tool, uninstall it. Fewer programs means a smaller attack surface.
• Keep it updated. Updates, often called patches, fix security flaws that have been discovered. Once a flaw is public, attackers look for machines that have not patched it. Turn on automatic updates for the OS, browser and apps wherever possible.

Installing should need the administrator account (from the last lesson). That pause is a feature: it makes you ask whether this program should be here at all.

The shortcut

Before any install, run the three-gate check: Is it from the real source? Do we really need it? Will it get updates? A "no" at any gate means stop.

After that, check the other side of the habit: are the till PC's OS and browser set to update automatically? An installed but unpatched browser is a bigger risk than most new programs.

Drills

Answer fast — trust the rule.

Remember

• Install from the real source, only what you need, and keep it updated.
• The three-gate check: real source, real need, real updates.
• Trap: cracked or pop-up downloads, and unpatched browsers and systems.