Summary
Budibase: SSRF in Automation Steps - Webhook, Zapier, N8N, Slack, Discord Bypass IP Blacklist
Budibase automation steps (outgoing webhook, Zapier, n8n, Slack, Discord, Make.com) make server-side HTTP requests to user-provided URLs using node-fetch directly, completely bypassing the IP blacklist protection that exists in the REST API integration. Additionally, the REST API blacklist itself defaults to empty when BLACKLIST_IPS is not configured.
Vulnerable Code
Automation Steps (No Blacklist)
All automation steps use fetch() directly without any IP validation:
packages/server/src/automations/steps/outgoingWebhook.ts line 69:
const response = await fetch(url, request) // No blacklist check
packages/server/src/automations/steps/zapier.ts line 34:
response = await fetch(url, {method: "post", ...}) // No blacklist check
packages/server/src/automations/steps/n8n.ts line 53:
response = await fetch(url, request) // No blacklist check
packages/server/src/automations/steps/slack.ts line 20:
response = await fetch(url, {method: "post", ...}) // No blacklist check
packages/server/src/automations/steps/discord.ts line 29:
response = await fetch(url, {method: "post", ...}) // No blacklist check
REST API Integration (Empty Default Blacklist)
packages/server/src/integrations/rest.ts line 684:
if (await blacklist.isBlacklisted(url)) {
throw new Error("Cannot connect to URL.")
}
But BLACKLIST_IPS env var defaults to undefined, so the blacklist is empty:
packages/backend-core/src/blacklist/blacklist.ts lines 39-45:
if (blackListArray?.length === 0) {
return false // Always passes when no IPs configured
}
Impact
- Automation steps: ANY user can create automations with webhook/Zapier/n8n/Slack/Discord steps pointing to internal IPs. These completely bypass the blacklist module
- REST API: Even when BLACKLIST_IPS is configured, it only blocks listed IPs. Default deployments have no protection.
- Cloud metadata:
http://169.254.169.254/latest/meta-data/accessible via any automation step - Internal services: Access databases, admin panels, Kubernetes API on private IPs
Untrusted input controls the target URL of a server-initiated request, which may reach internal services not otherwise accessible from outside. Typical impact: access to internal metadata services, internal APIs, or cloud credentials.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Already deployed Kodem?
See it in your environmentNew to Kodem? Get a demo →Remediation advice
- Apply blacklist checks to ALL outbound HTTP requests, including automation steps
- Add hardcoded default private IP ranges (127.0.0.0/8, 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16, 169.254.0.0/16)
- Use a centralized HTTP client wrapper instead of direct
fetch()calls - SSRF protection should be on by default, not opt-in via environment variable
Frequently Asked Questions
- What is CVE-2026-35219? CVE-2026-35219 is a high-severity server-side request forgery (SSRF) vulnerability in @budibase/server (npm), affecting versions < 3.41.3. It is fixed in 3.41.3. Untrusted input controls the target URL of a server-initiated request, which may reach internal services not otherwise accessible from outside.
- Which versions of @budibase/server are affected by CVE-2026-35219? @budibase/server (npm) versions < 3.41.3 is affected.
- Is there a fix for CVE-2026-35219? Yes. CVE-2026-35219 is fixed in 3.41.3. Upgrade to this version or later.
- Is CVE-2026-35219 exploitable, and should I be worried? Whether CVE-2026-35219 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-35219 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-35219? Upgrade
@budibase/serverto 3.41.3 or later.