Software updates: a practical guide

This is one of those topics that looks small until it costs you something. This guide covers what software updates actually involves, where it usually goes wrong, and how to tell whether yours is in reasonable shape.

The cheapest security work is the boring kind done on a schedule. Nothing below assumes a large team or a large budget — most of it is a decision somebody has to make and then write down.

Why this earns attention

Most breaches exploit a fix that already existed. None of that requires a large budget, only a decision and someone to own it. The version that survives contact with a real deadline is the simple one.

For most businesses the question is not whether this matters but how much of it is worth doing right now. That depends on what you are trying to achieve in the next few months, not on best practice in the abstract. It is worth being explicit about, because assumptions differ quietly.

How we handle it

Schedule updates rather than reacting to incidents. That sounds obvious written down. It is still the thing most often skipped. Budget a little time for it every quarter and it never becomes a project of its own.

Security is a maintenance habit rather than a purchase, which is why it drifts. The version that works in practice is usually less elaborate than the version described in the guides.

Staging first prevents the update becoming the outage. The teams that handle this well are rarely the ones with the biggest budgets. Check it against what you would want a competitor's site to get wrong.

A working checklist

If you want a quick read on where you stand, work through this. Anything you cannot answer confidently is where to start.

• Most breaches exploit a fix that already existed
• Schedule updates rather than reacting to incidents
• Staging first prevents the update becoming the outage
• Someone is named as the owner, not just assumed to be
• There is a date in the calendar to review it again
• The decision and the reasoning behind it are written down somewhere findable
• You could explain the current setup to a new hire in five minutes

What to watch for

The most common failure is not doing this badly. It is doing it once, during a launch, and never revisiting it. Circumstances move, the setup does not, and the gap widens quietly until something breaks or somebody notices the numbers.

• It was configured during a launch and has not been touched since
• Different people in the business believe different things are true about it
• There is no way to tell whether the last change helped or hurt
• The only person who understands it has left, or is about to

The realistic threat for most small businesses is automated and opportunistic, not targeted. This is the sort of thing that compounds, quietly, in both directions.

How we approach it

On our projects this gets handled during the build rather than added afterwards, because retrofitting it costs several times more than including it. We write down what was decided and why, so the next person to touch it is not guessing.

If you are working with someone else, the questions worth asking are simple: who owns this, how will we know it is working, and what happens when it needs to change?

Turning this into a decision

Pick the single item from the checklist above that would cause the most trouble if it turned out to be wrong. Fix that one, confirm it worked, then move on. Worth checking on your own setup before it becomes someone else's problem to fix.