Table of Contents

• supported versions
• cryptographic foundation
• threat model
• reporting a vulnerability
• scope

COVCOM follows a rolling support policy. When a security fix ships, the previous version is deprecated immediately. Only the current release is supported.

Deprecated versions receive no patches. Upgrade promptly.

COVCOM releases in tandem with leviathan-crypto. The ratchet module (PR #12) ships alongside COVCOM v1.0.0. A vulnerability in either project triggers a coordinated release of both.

All cryptographic operations in COVCOM are provided by leviathan-crypto, a zero-dependency TypeScript/WASM library by the same author. There are no third-party cryptographic dependencies.

The active primitive set:

The protocol implements the Sparse Post-Quantum Ratchet from the Signal Double Ratchet spec (§5, Revision 4) with a Sender Keys group messaging model.

The protocol provides:

• Message confidentiality against passive and active network adversaries
• Forward secrecy — past messages are unrecoverable from current state
• Post-compromise security at every KEM ratchet boundary
• Harvest-now-decrypt-later resistance via ML-KEM-768
• Enumeration resistance via a 2^128 room secret space
• Session anonymity — no persistent identity keys visible to the server

The protocol does not protect against:

• Endpoint compromise (malware, physical device access)
• Traffic analysis (timing, message volume, session duration)
• A server that lies about room membership
• Cryptographic deniability
• Multi-session correlation by out-of-band means

See the full Dolev-Yao style adversary analysis in THREAT-MODEL.md.

Use GitHub's private vulnerability reporting form: https://github.com/xero/covcom/security/advisories/new

This opens a private channel between you and the maintainer, and you will receive a response promptly. If the vulnerability is confirmed, we will collaborate to fully understand the issue, including a review of proposed fixes, so you can track and validate firsthand. Before any public advisory is published, we will agree on a coordinated disclosure timeline. After disclosure, you are encouraged to publish your own write-up, blog post, or research notes, for full hacker scene credit.

If you prefer to contact the maintainer directly:

• Email: x﹫xero.style · PGP: 0xAC1D0000
• Matrix: x0﹫rx.haunted.computer

In scope:

• Vulnerabilities in COVCOM's web client, CLI, or server
• Vulnerabilities in the COVCOM wire protocol or session handshake
• Cryptographic weaknesses in the ratchet implementation or key derivation
• Vulnerabilities in leviathan-crypto primitives or the WASM layer
• Protocol design flaws — if the design itself is unsound, that counts
• Dependency vulnerabilities that affect COVCOM's security properties
• Invite format weaknesses (enumeration, forgery, replay)

Out of scope:

• Bugs in leviathan-crypto unrelated to COVCOM's use of it. Please Report those in the leviathan-crypto repository
• The non-goals listed in the threat model: endpoint security, traffic analysis, server availability attacks, multi-session correlation
• Attacks requiring physical access to a participant's device
• Social engineering attacks against participants
• APT-level nation-state adversaries with quantum computing capability today (ML-KEM-768 addresses future quantum, not present-day state actors with unlimited classical resources)
• Spam or denial-of-service against publicly hosted instances