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+# Security Policy
+
+DeepSeek TUI is a coding agent with direct access to file operations, shell execution, and the network. Security disclosures are taken seriously.
+
+## Supported Versions
+
+Only the latest stable release receives security patches. No backports to older versions.
+
+| Version | Supported |
+|---|---|
+| latest stable | :white_check_mark: |
+| < latest | :x: |
+
+Check the [releases page](https://github.com/Hmbown/DeepSeek-TUI/releases) for the current version.
+
+## Reporting a Vulnerability
+
+**Do not open a public GitHub issue for security vulnerabilities.**
+
+Report privately via one of:
+
+- **Email**: [hmbown.dev@gmail.com](mailto:hmbown.dev@gmail.com) — include `[SECURITY]` in the subject line
+- **GitHub private advisory**: [github.com/Hmbown/DeepSeek-TUI/security/advisories/new](https://github.com/Hmbown/DeepSeek-TUI/security/advisories/new)
+
+Include in your report:
+
+- A description of the vulnerability and the impact if exploited
+- Steps to reproduce or a proof of concept
+- Affected versions and configuration details
+- Any suggested mitigation (optional)
+
+## Response Timeline
+
+| Phase | Target |
+|---|---|
+| Acknowledgment | Within 48 hours of receipt |
+| Assessment | Within 5 days — triage severity, scope, and fix approach |
+| Patch (critical) | Within 14 days from assessment |
+| Patch (moderate/low) | Next feature release or per-maintainer timeline |
+| Disclosure | After patch is shipped and users have had time to update |
+
+You will receive status updates at each phase. If the timeline slips, we will communicate the reason and the revised estimate.
+
+## Scope
+
+### In scope (what counts)
+
+- Remote code execution through crafted prompts or model responses
+- Sandbox escape — breaking out of the YOLO-mode workspace boundary or shell `cwd` confinement
+- Credential leak — exfiltration of API keys, tokens, or environment secrets
+- Arbitrary file read/write outside the intended workspace (`PathEscape` bypass)
+- SSRF via `fetch_url` or `web_search` against internal network endpoints
+- Unauthorised MCP server access or tool invocation
+
+### Out of scope
+
+- Social engineering of the maintainer or contributors
+- Denial of service / rate-limit exhaustion against the DeepSeek API
+- Vulnerabilities in third-party dependencies (report to the upstream project)
+- Attacks requiring physical access to the victim's machine
+- Theoretical ML-model injection attacks not demonstrated in the DeepSeek TUI context
+
+If you are unsure whether a bug is in scope, report it anyway. We will triage and respond.
+
+## Hall of Fame
+
+We maintain a hall of fame for reporters who submit verified security vulnerabilities. To be credited, include your preferred name / handle in the report.
+
+*No entries yet — be the first.*