Security & privacy
Your secret is encrypted in your own browser before it leaves your device. We never see it, we can't read it, and once it has been opened it is gone.
How your secret is protected
- Encrypted on your device. When you create a link, your browser encrypts the message with AES-256-GCM, using a brand-new random 256-bit key. Only the encrypted message is sent to our server.
- The key never reaches us. The key is the part of the link after the
#. Browsers never send that part to a server, so we only ever hold scrambled data that we cannot decrypt. - Optional password. With a password, the key is combined with your password (PBKDF2-SHA-256 with 600,000 rounds, then HKDF). Someone who intercepts the link still can't read the message without the password. Share the password through a different channel than the link.
- Tamper-proof. AES-GCM detects any change to the encrypted message. A damaged or altered message is refused instead of shown.
Quantum-resistant
- Quantum computers threaten public-key cryptography such as RSA and elliptic curves. Wowsers doesn't use those for your message: it relies only on symmetric 256-bit encryption, which stays out of reach of quantum computers as well.
- The connection to our server uses hybrid post-quantum key exchange (X25519 combined with ML-KEM-768, the NIST standard), so recording our traffic today and decrypting it later won't work either. Browsers that don't support it yet fall back to the classic method.
- The website's certificate is still a classic one: post-quantum certificates aren't available yet from any public certificate authority.
One-time and self-destructing
- Every link works once. The moment the recipient opens it, the encrypted message is deleted from our server.
- Unopened messages are deleted automatically when they explode: after 1 hour to 7 days, whichever you chose.
- Deleted means deleted. We don't just mark a message as deleted: we overwrite it with zeros, so it can't be recovered from our database afterwards.
- On the recipient's side the text can't be selected: copying it with Copy and destroy! (or Ctrl+C) removes it from the page.
What we store
For each message, until it is opened or explodes:
- the encrypted message,
- the random values needed to decrypt it with the key (never the key itself),
- whether a password is needed (never the password itself),
- when it was created and when it explodes.
We don't store your name, email address or IP address with a message. There are no accounts, no cookies, no analytics, no advertising and no third-party scripts or fonts: every file on this site comes from our own server.
Server logs and IP addresses
- Our web server records the IP address, time and browser type of requests for the site's pages, images and scripts. We keep these logs for 14 days, for security and to fix problems, and then they are deleted automatically.
- Requests that involve a message (opening a link, creating or reading a message) are not logged, so the logs can't tell which message anyone sent or read.
- To prevent abuse we limit how many messages one IP address can create or open. For that the IP address is kept in memory for at most 10 minutes and never written to disk.
In your browser
After you create a link, your browser remembers its code (not the key) for 5 minutes in local storage. If you open your own link in that time, it expires, so you can't use up the recipient's one-time view by accident. Nothing else is stored in your browser.
Where it runs
Wowsers runs on a server in Nuremberg, Germany (EU). Nothing is shared with or sold to anyone.
What we can't protect against
- The recipient can still take a photo or screenshot, or type the text over.
- The link itself is the key. Send it through a channel you trust, such as an end-to-end encrypted messenger. Anyone who gets hold of the link (and the password, if you set one) before the recipient can read the message, and then the recipient finds it gone.
- If your device or the recipient's device is infected with malware, no website can keep a secret safe.