Cryptgeon on Ubuntu 24.04 LTS

Overview

Cryptgeon is a self hosted service for handing someone a password, an API key, a recovery phrase or a file exactly once. The sender pastes the secret, chooses how many times it may be opened or how long it may live, and shares a single link. When the recipient opens it the note is destroyed. What makes it different from a paste bin is that the server cannot read what it stores: the note is encrypted in the sender's browser and the decryption key travels in the fragment of the share link, the part browsers never send to any server. The instance holds ciphertext alone, so even full administrative access to the machine and its datastore cannot recover a note. Nothing persists to disk either, because the note store runs entirely in memory with snapshots and append only logging switched off. There are no accounts, no login and no administrator console: anyone who can reach the page can create a note, and only the link holder can read it. Text and file uploads are both supported, with a bounded maximum size.

Common uses

• Hand a password or API key to a colleague or a client without leaving it sitting in chat or email
• Share a recovery phrase, certificate or credentials file that must be readable exactly once
• Give a team a private, self hosted alternative to public one time secret websites

See it running

Real screenshots taken while testing this image against its deployment guide.