Hex Security Basics

Hex Security Basics

Overview

Hex is a collaborative data analytics platform where notebooks query production databases, generate visualizations, and share results across teams. Security concerns center on API token management (read vs run scopes), protecting database connection credentials embedded in Hex projects, and ensuring query results containing sensitive business data are not leaked through logs or exports. A compromised run-scope token can trigger arbitrary queries against connected databases.

API Key Management

function createHexClient(scope: "read" | "run"): { token: string; baseUrl: string } {
  const envVar = scope === "run" ? "HEX_RUN_TOKEN" : "HEX_READ_TOKEN";
  const token = process.env[envVar];
  if (!token) {
    throw new Error(`Missing ${envVar} — store in secrets manager, never in code`);
  }
  // Run tokens can trigger queries — use read tokens for monitoring
  console.log(`Hex client initialized with ${scope} scope (token suffix: ${token.slice(-4)})`);
  return { token, baseUrl: "https://app.hex.tech/api/v1" };
}

Webhook Signature Verification

import crypto from "crypto";
import { Request, Response, NextFunction } from "express";

function verifyHexWebhook(req: Request, res: Response, next: NextFunction): void {
  const signature = req.headers["x-hex-signature"] as string;
  const secret = process.env.HEX_WEBHOOK_SECRET!;
  const expected = crypto.createHmac("sha256", secret).update(req.body).digest("hex");
  if (!signature || !crypto.timingSafeEqual(Buffer.from(signature), Buffer.from(expected))) {
    res.status(401).send("Invalid signature");
    return;
  }
  next();
}

Input Validation

import { z } from "zod";

const HexRunRequestSchema = z.object({
  project_id: z.string().uuid(),
  input_params: z.record(z.string(), z.unknown()).optional(),
  notify_on_completion: z.boolean().default(false),
  update_cache: z.boolean().default(false),
});

function validateHexRunRequest(data: unknown) {
  return HexRunRequestSchema.parse(data);
}

Data Protection

const HEX_SENSITIVE_FIELDS = ["db_connection_string", "query_results", "api_token", "input_params", "export_url"];

function redactHexLog(record: Record<string, unknown>): Record<string, unknown> {
  const redacted = { ...record };
  for (const field of HEX_SENSITIVE_FIELDS) {
    if (field in redacted) redacted[field] = "[REDACTED]";
  }
  return redacted;
}

Security Checklist

• API tokens stored in secrets vault, never in code
• Read-only tokens for monitoring, run tokens for orchestration only
• Token expiration set to 90 days maximum
• Separate tokens per environment (dev/staging/prod)
• Pre-commit hook blocks hex_token_* patterns
• Database connection credentials managed in Hex workspace settings
• Query result exports reviewed for sensitive data before sharing
• Notebook sharing permissions audited per team

Error Handling

Prerequisites

• A threat model naming token custodians, project/data owners, untrusted parameters, incident owner, and approved secret manager.
• Low-privilege sandbox credentials and a project that contains no production-sensitive fixtures for verification.
• Rotation, revocation, project-disable, and cancellation runbooks with tested rollback.

Instructions

1. Scope credentials by environment and project, inject them from the secret manager, and deny unknown scope or destination.
2. Validate parameters, origin, size, and allowed project before starting a run; quarantine failures with opaque correlation IDs.
3. Verify webhook authenticity before parsing, reject stale/replayed events, and store only bounded redacted envelopes.
4. Test least-privilege and denied access with sandbox projects after every authorization or client change.
5. Revoke suspected credentials immediately, cancel affected runs if integrity is uncertain, and preserve only redacted incident evidence.

Output

Return a security receipt with environment, project scope, secret-reference version, validation/authorization outcomes, rotation/revocation state, correlation ID, and rollback action. Never include tokens, SQL, output, or raw events.

Examples

env=staging; project=proj-sandbox-12; secret_ref=runner-v12; parameter_validation=pass; access=least-privilege; rollback=run-cancelled is an auditable control result.

Resources

• Hex API Authentication
• OWASP API Security Top 10

Next Steps

See hex-prod-checklist.