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SECURITY.md

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+# Security Policy
+
+## Supported Versions
+
+This is a personal portfolio project, so there is no formal long-term support schedule. Security
+fixes are applied to the current main branch when issues are confirmed and within the practical
+maintenance capacity of the project.
+
+## Reporting A Vulnerability
+
+Please do not open a public issue for a security vulnerability.
+
+Report security concerns privately to the repository maintainer. Include as much detail as you can:
+
+- a description of the vulnerability;
+- steps to reproduce the issue;
+- affected routes, commands, files, or configuration;
+- the potential impact;
+- any suggested fix or mitigation, if you have one.
+
+You can expect a best-effort response acknowledging the report, followed by validation and a fix when
+the issue is reproducible and in scope.
+
+## Security Scope
+
+The most important security areas for this project are:
+
+- local authentication and session handling;
+- watchlist and playback progress data;
+- playback proxy tokens and signed stream access;
+- subtitle and playlist proxying;
+- external provider integration boundaries;
+- SQLite database access and migrations;
+- configuration loaded from environment variables or `.env` files.
+
+Reports involving these areas are especially useful.
+
+## Out Of Scope
+
+The following are generally out of scope unless they expose a direct application vulnerability:
+
+- issues that require full local machine access;
+- denial-of-service reports against a local development server;
+- vulnerabilities in third-party services outside this repository;
+- missing production hardening for deployments that are not documented or supported by the project;
+- social engineering or physical attacks.
+
+## Operational Notes
+
+This application is designed to be self-hosted and local-first. If you deploy it beyond a private
+local environment, you are responsible for the surrounding production controls, including TLS, network
+access, backups, secrets management, reverse proxy configuration, logging retention, and dependency
+monitoring.
+
+Use a strong `PLAYBACK_PROXY_SECRET` if playback proxy token signing is enabled. Do not commit real
+secrets, provider tokens, session data, or production databases to the repository.
+
+## Dependency Security
+
+Dependencies are managed through Go modules and Bun. When updating dependencies, run the normal local
+checks before merging:
+
+```bash
+just check
+```
+
+Security-related dependency updates should be kept small and reviewed separately when possible.