Secure and Confidential Sharing

• End-to-end encrypted sharing of text and files.
• Links self-destruct after the first read, ensuring content is only viewed once.
• Optional custom encryption keys for enhanced security.
• Files up to 10 MB can be attached and are encrypted with the same key as the text.
• Content is stored on secure servers in Europe and is automatically deleted upon first access or expiration.
• Provides cryptographic proof of deletion, verifiable independently.
• Offers a secure alternative to sharing sensitive information via email or SMS.
• Integrates with Proxae for blockchain timestamp certification of ideas and creations.

protonURL is designed to provide a secure and confidential content-sharing service. The service ensures that sharing links self-destruct after the first access, meaning that shared data can only be viewed once. This limits access to the shared data and reduces the risk of leaks or misuse. Data is encrypted with AES-256-CBC encryption, with a different key and IV used for each content. Attached files are also encrypted and stored outside the web directory, making them inaccessible via HTTP. The original filename is also encrypted separately. Both the file and its metadata are permanently deleted upon first access or expiration. The service also offers deletion proofs that certify that a URL's content has been permanently destroyed, which can be cryptographically signed and verified independently.