Sectify.io is an app that lets you encrypt a file and generate an expiring link for it. The app is completely free and doesn't require any sign-up to download files.

What is a file and how do you send it?

To send a file you just need to select the file you want to upload and the recipient to send it to. Next, choose a time when you want the link to expire and when you want the link to expire. You can use multiple links to make sharing files with multiple people more convenient. The links generated are ephemeral and only last for 7 days. After that, the link will stop working.

If a recipient’s email has been compromised, an attacker would have access to all the recipient’s attachments, including the ones you may have sent to them.