Skip to main content

Security & privacy

Credentials​

IMAP/SMTP passwords and OAuth refresh tokens are encrypted with an asymmetric envelope scheme (RSA envelope encryption with AES-256-GCM) before they're stored. The components that serve the portal and the MCP endpoint only ever hold the public key — they can encrypt new credentials, but never decrypt existing ones. Recovering the credentials from outside is technically impossible.

Mail content​

Mail content is never persisted on our side. On a tool call the requested message is loaded directly from your source mailbox (IMAP or Microsoft Graph), returned to the caller, and then dropped. Attachment download URLs are cryptographically signed (HMAC-SHA256) and valid for at most 15 minutes.

Prompt injection​

Because inboxmcp forwards mail content into an AI model, prompt injection via received mail is a real threat model. How inboxmcp defends against it, and what users can do themselves, is covered on a dedicated page: Prompt injection.

Audit log (Business)​

Every MCP tool call is recorded with timestamp, tool, mailbox, client and result. Business accounts can view and filter the audit log in the portal. Download / export is on the roadmap.

Hosting​

inboxmcp.io runs on our own infrastructure in German data centres and is built for high availability and scale.

Privacy policy & DPA​