Do not open a public issue for a vulnerability that could expose credentials, player data, administrative access, or a running server. Use the repository's private GitHub Security Advisory form instead:

https://github.com/faratech/deltamud/security/advisories/new

Include the affected revision, configuration, reproduction steps, impact, and any proof-of-concept material that can be shared safely. Never include live passwords, database URLs, private player communications, or production data.

Security fixes target the current main branch and the currently deployed Rust release. The legacy C server is retained as a compatibility oracle and is not a supported public production target.

• The game world has one authoritative owner; edge transports and HTTP helpers cannot mutate it directly.
• Production database configuration fails closed and secrets are never logged.
• Legacy password hashes may be verified for migration, but new hashes use the current password policy and are upgraded after successful authentication.
• OLC and runtime persistence publish through checked durable replacement; a failed save retains both the previous durable file and the pending edit.
• Plain Telnet is a compatibility transport. Production credentials should use a reviewed TLS endpoint.
• Copyover accepts only validated snapshots, sockets, and executable paths.

Changes affecting these invariants require focused regression tests plus the full release gate documented in rust-mud/docs/RUNBOOK.md.