Report suspected vulnerabilities through GitHub's private vulnerability reporting on this repository: open the Security tab and choose Report a vulnerability. That channel is private between you and the maintainer. Please do not open a public issue for a suspected vulnerability.

This is a single-maintainer, pre-1.0 prototype. There is no guaranteed response time; reports are read and answered as time allows. Do not wait for a fix before protecting yourself.

Only the current main branch and the most recent tagged release receive fixes. There are no long-term-support branches.

deltasafe is an authenticated file-transfer tool for a trusted LAN. In scope:

• Breaking the confidentiality or integrity of a transfer between two peers that share a key.
• Producing a frame that authenticates without the shared key, or forging a final status.
• Causing a receiver to publish a file that does not match the sender's declared size and BLAKE3 digest.
• Escaping the receive root through a crafted relative path, a symlink parent, or a destination collision that overwrites an existing file.
• A denial of service against the receiver from an unauthenticated peer that is materially worse than the protocol's bounded frame and header sizes imply.

These are documented non-goals, not vulnerabilities:

• No certificate-based peer identity, no TLS, and no forward secrecy.
• No durable replay protection across receiver restarts.
• No protection against a local administrator who can modify the receive directory during a transfer, or against OS-specific TOCTOU races that standard-library path checks cannot close.
• No disk-quota or general resource-exhaustion protection beyond the bounded frame and header sizes.
• Anyone who already holds the shared password or key is trusted by design.

This project has not been independently audited or penetration-tested. The test suite and the recorded loopback evidence under docs/validation/ show that specific scenarios behave as documented. They are not a general security certification.

Keep the receiver on a network you control, and do not expose the listening port directly to the public internet.