KostromAi44 is built with a security-first posture, implementing defensive design principles across every tier of the full-stack system. This guide documents the active threat mitigation models, API key management guidelines, and secure deployment configurations.

Every critical secret utilized by KostromAi44 — including LLM vendor credentials (Gemini, OpenAI, Anthropic, Sentry, DB strings, session tokens) — must be declared environment-side.

1. Never Commit Secrets to Git: High-risk environment details must always be ignored. The .env file must never be committed. Always maintain .env.example with blank placeholders.
2. Server-Side-Only Secrets API (No VITE_ Expositions): Sensitive tokens such as GEMINI_API_KEY are read exclusively by Node.js server threads and kept inside memory limits on our backend handlers. They are never prefixed with VITE_ (which would bundle them into client-side build modules accessible via browser devtools).
3. Lazy SDK Initialization: SDKs that require API credentials are bound lazily in request contexts rather than module load time. If a key becomes invalid or missing, server processes continue running smoothly with degraded fallback routes instead of suffering start crashes.

When users construct workflows containing Tool Nodes (custom JS scripts) or dynamic API connectors, malicious chains might attempt to issue target-probing requests inwards to your secure network infrastructure. KostromAi44 deploys a custom validation layer (src/utils/ssrf-validator.js) that enforces:

• Host Filtering: All externalized request destinations requested by tools are validated.
• Network Exclusion List: Requests resolving to localhost, loopbacks (127.0.0.1), metadata endpoints (169.254.169.254 for AWS/GCP/Azure metadata harvesting), and private subnets (10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16) are blocked instantly.

In typical production networks, debug logs often leak sensitive customer tokens through stacktraces or raw parameters. Our logging system intercepts standard logging output streams:

• Checks all outgoing strings in debug messages and API logs for security keys (api_key, authorization, password, jwt).
• Replaces secret contents with the safe string ***MASKED*** dynamically before write streams commit messages to system logging aggregators.

Code executed inside custom Tool Nodes must never have access to the underlying Node.js runtime process.

• Custom codes run inside isolated VMs using Node.js Worker Threads.
• The sandboxed worker is stripped of access to dangerous global variables (such as process, require, physical globalThis references, or Node's file system fs APIs).
• Network connections are heavily rate-limited and timeout boundaries are enforced (e.g. max execution time of 2 seconds) to easily withstand infinite loop lockups or memory leak exhaustion vector attacks.

For maximum perimeter security when deploying KostromAi44 to external networks:

• Force encryption on all connections by configuring a secure Reverse Proxy (Nginx, Cloudflare Tunnel, or Google Cloud Load Balancer) to terminate TLS traffic.
• Enforce HTTP Strict Transport Security (HSTS) to automatically shift plaintext browser interactions to SSL/TLS.
• Database clients must require strict SSL certificates (sslmode=verify-full) to protect database socket handshakes from middleman listener attacks (MitM).

• Ingress Firewall: Only standard external ports (3000 or 443) should be exposed to public networks. Keep individual API routing, internal test gateways, or database sockets blocked behind firewall perimeters.
• VPC Peering: Database backends must run in private subnets, only accepting traffic coming from the container subnets of KostromAi44.

An integrated sliding window rate-limiter protects backend handlers against brute-force attacks and token consumption loops. For extreme enterprise needs, deploy a distributed rate-limiter (e.g., Redis-backed rate limits) as outlined in the Deployment Guide.