File permissions: who can open it, and who can change that

Almost every accidental disclosure inside a company is a permissions problem rather than an attack: a folder shared with the whole organisation when it should have gone to four people, a link that outlived the project, a leaver whose access was never removed. File permissions are the control that actually decides exposure, and they are usually the least reviewed thing in the building.

Three questions file permissions must answer

• Who can open this — named people or a named group, never "everyone with the link" by default.
• Who can change it, which is a separate question from who can read it and deserves a shorter list.
• Who can change the permissions themselves. This is the one people forget, and it is how a tightly scoped folder quietly becomes open.

Grant to groups, not to people

Permissions given to individuals look tidy on the day and decay immediately: somebody changes role, somebody joins, somebody leaves, and nothing in the file system knows. Granting to a group means access follows membership, so a single change to the group fixes every folder at once. The cost is that groups need owners and a reason to exist — a group called "project-x-readers" with no owner is just a list of individuals with extra steps.

Inheritance is a feature until it is a surprise. Before moving a folder, check what it will inherit at the destination — the commonest real-world exposure is not a bad permission but a correct permission applied to the wrong parent.

Links, guests and expiry

1. Default new documents to the team rather than to anyone with the link.
2. Give every external share an expiry date at the moment you create it, not later.
3. Keep a list of current external collaborators and reconcile it against real suppliers and clients quarterly.
4. Prefer named guest accounts over anonymous links where the content matters — a link cannot be attributed, a guest can.
5. Remove access on a leaver's last day and record that it was done.

Reviewing without it becoming a project

A full permissions audit is miserable and therefore never happens twice. A narrow one works: pick the folders holding the material you would least like to see forwarded, list who currently has access, and ask the owner to confirm each entry. Fifteen minutes per folder, four folders a quarter, and you will find something every time — usually a group that was correct two reorganisations ago.

Ettex Storage keeps folders with per-person and per-group permissions, named accounts rather than anonymous links, and an access log you can export for the review above. Pairing it with a written access control policy means the review has something to check against rather than relying on whoever remembers the original intent.