What Is security.txt?
security.txt is a standardized text document that website operators publish at /.well-known/security.txt. It works much like a robots.txt – just for security matters: if someone finds a vulnerability on your website, they don't have to search for a suitable contact; instead they immediately find a clearly defined way to make a responsible disclosure.
The format is standardized in RFC 9116 and is used by major providers such as Google, GitHub, and Cloudflare, among others.
Example of a security.txt
Here's what a minimal, RFC-compliant security.txt could look like:
Contact: mailto:info@wacon.de
Expires: 2027-08-21T00:00:00.000Z
Encryption: https://www.wacon.de/pgp-key.txt
Preferred-Languages: en, de
Canonical: https://www.wacon.de/.well-known/security.txt