https://[project].supabase.co/functions/v1/[function-name]

Audit Edge Functions on my Supabase project

Test the process-payment Edge Function for security issues

═══════════════════════════════════════════════════════════
 EDGE FUNCTIONS AUDIT
═══════════════════════════════════════════════════════════

 Project: abc123def.supabase.co
 Endpoint: https://abc123def.supabase.co/functions/v1/

 ─────────────────────────────────────────────────────────
 Function Discovery
 ─────────────────────────────────────────────────────────

 Discovery Method: Common name enumeration + client code analysis

 Functions Found: 5

 ─────────────────────────────────────────────────────────
 1. hello-world
 ─────────────────────────────────────────────────────────

 Endpoint: /functions/v1/hello-world
 Method: GET, POST

 Authentication Test:
 ├── Without JWT: ✅ 200 OK
 └── Status: ℹ️ Public function (no auth required)

 Response:
 ```json
 {"message": "Hello, World!"}

# As user A, request user B's data
curl https://abc123def.supabase.co/functions/v1/get-user-data?user_id=user-b-id \
  -H "Authorization: Bearer [user-a-token]"

# Returns user B's data!

// In Edge Function
const { user_id } = await req.json();
const jwt_user = getUser(req); // From JWT

// Verify ownership
if (user_id !== jwt_user.id) {
  return new Response('Forbidden', { status: 403 });
}

// Verify admin role
const user = getUser(req);
const { data: profile } = await supabase
  .from('profiles')
  .select('is_admin')
  .eq('id', user.id)
  .single();

if (!profile?.is_admin) {
  return new Response('Forbidden', { status: 403 });
}

{
  "error": "Invalid signature",
  "expected": "sha256=abc123...",
  "received": "sha256=xyz789..."
}

// Generic error, log details server-side
if (!validSignature) {
  console.error(`Invalid signature: expected ${expected}, got ${received}`);
  return new Response('Unauthorized', { status: 401 });
}

## Common Function Vulnerabilities

| Vulnerability | Description | Severity |
|---------------|-------------|----------|
| No auth | Function accessible without JWT | P0-P2 |
| IDOR | User can access other users' data | P0 |
| Missing role check | Regular user accesses admin functions | P0 |
| Input injection | User input not validated | P0-P1 |
| Info disclosure | Errors reveal internal details | P1-P2 |
| CORS misconfigured | Accessible from unintended origins | P1-P2 |

## Function Discovery Methods

### 1. Client Code Analysis

```javascript
// Look for function invocations in client code
supabase.functions.invoke('function-name', {...})
fetch('/functions/v1/function-name', {...})

404 Not Found → Function doesn't exist
401 Unauthorized → Function exists, needs auth
200 OK → Function exists, accessible

{
  "functions_audit": {
    "timestamp": "2025-01-31T14:30:00Z",
    "functions_found": 5,
    "findings": [
      {
        "function": "get-user-data",
        "severity": "P0",
        "vulnerability": "IDOR",
        "description": "Any authenticated user can access any user's data",
        "remediation": "Verify user owns requested resource"
      },
      {
        "function": "admin-panel",
        "severity": "P0",
        "vulnerability": "Privilege Escalation",
        "description": "No role check, any authenticated user is admin",
        "remediation": "Add admin role verification"
      }
    ]
  }
}

import { createClient } from '@supabase/supabase-js'

Deno.serve(async (req) => {
  // Get JWT from header
  const authHeader = req.headers.get('Authorization');
  if (!authHeader) {
    return new Response('Unauthorized', { status: 401 });
  }

  // Verify JWT with Supabase
  const supabase = createClient(
    Deno.env.get('SUPABASE_URL')!,
    Deno.env.get('SUPABASE_ANON_KEY')!,
    { global: { headers: { Authorization: authHeader } } }
  );

  const { data: { user }, error } = await supabase.auth.getUser();
  if (error || !user) {
    return new Response('Unauthorized', { status: 401 });
  }

  // User is authenticated
  // ...
});

// For user-specific resources
const requestedUserId = body.user_id;
const authenticatedUserId = user.id;

if (requestedUserId !== authenticatedUserId) {
  return new Response('Forbidden', { status: 403 });
}

// Check admin role
const { data: profile } = await supabase
  .from('profiles')
  .select('role')
  .eq('id', user.id)
  .single();

if (profile?.role !== 'admin') {
  return new Response('Forbidden', { status: 403 });
}

import { z } from 'zod';

const PaymentSchema = z.object({
  amount: z.number().positive().max(10000),
  currency: z.enum(['usd', 'eur', 'gbp']),
  description: z.string().max(200).optional()
});

// Validate input
const result = PaymentSchema.safeParse(body);
if (!result.success) {
  return new Response(
    JSON.stringify({ error: 'Invalid input' }),
    { status: 400 }
  );
}

{
  "evidence_id": "FN-001",
  "timestamp": "2025-01-31T11:10:00Z",
  "category": "functions-audit",
  "type": "idor_vulnerability",
  "severity": "P0",

  "function": "get-user-data",
  "endpoint": "https://abc123def.supabase.co/functions/v1/get-user-data",

  "tests": [
    {
      "test_name": "auth_required",
      "request": {
        "method": "GET",
        "headers": {},
        "curl_command": "curl '$URL/functions/v1/get-user-data'"
      },
      "response": {"status": 401},
      "result": "PASS"
    },
    {
      "test_name": "idor_test",
      "description": "As user A, request user B's data",
      "request": {
        "method": "GET",
        "url": "$URL/functions/v1/get-user-data?user_id=user-b-id",
        "headers": {"Authorization": "Bearer [USER_A_TOKEN]"},
        "curl_command": "curl '$URL/functions/v1/get-user-data?user_id=user-b-id' -H 'Authorization: Bearer [USER_A_TOKEN]'"
      },
      "response": {
        "status": 200,
        "body": {"id": "user-b-id", "email": "[REDACTED]", "data": "[REDACTED]"}
      },
      "result": "VULNERABLE",
      "impact": "Any authenticated user can access any other user's data"
    }
  ],

  "remediation": "Add ownership check: if (user_id !== jwt_user.id) return 403"
}

{
  "evidence_id": "FN-002",
  "timestamp": "2025-01-31T11:15:00Z",
  "category": "functions-audit",
  "type": "privilege_escalation",
  "severity": "P0",

  "function": "admin-panel",

  "test": {
    "description": "Regular user accessing admin function",
    "request": {
      "method": "GET",
      "headers": {"Authorization": "Bearer [REGULAR_USER_TOKEN]"},
      "curl_command": "curl '$URL/functions/v1/admin-panel' -H 'Authorization: Bearer [REGULAR_USER_TOKEN]'"
    },
    "response": {
      "status": 200,
      "body": {"admin_data": "[REDACTED]"}
    },
    "result": "VULNERABLE",
    "impact": "Any authenticated user has admin access"
  }
}