CVE-2025-59434
📋 TL;DR
An authenticated vulnerability in Flowise Cloud allowed free-tier users to access sensitive environment variables from other tenants via the Custom JavaScript Function node. This exposed secrets like API keys and credentials, leading to full cross-tenant data exposure. Only Flowise Cloud users on the free tier prior to August 2025 were affected.
💻 Affected Systems
- Flowise Cloud
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Attackers steal all tenant secrets (API keys, cloud credentials, tokens), leading to unauthorized access to external services, data breaches, financial loss, and complete compromise of affected cloud accounts.
Likely Case
Malicious users exfiltrate sensitive environment variables from other tenants, potentially accessing their AI models, cloud resources, and databases.
If Mitigated
With proper access controls and tenant isolation, impact is limited to authorized data access only.
🎯 Exploit Status
Exploitation requires authenticated access but is straightforward via the Custom JavaScript Function node.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: August 2025 Cloud-Hosted Flowise
Vendor Advisory: https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-435c-mg9p-fv22
Restart Required: Yes
Instructions:
1. Upgrade to August 2025 Cloud-Hosted Flowise. 2. No action needed for self-hosted installations. 3. Cloud users are automatically updated.
🔧 Temporary Workarounds
Upgrade to paid tier
allMove from free tier to paid tier where tenant isolation is properly enforced.
Disable Custom JavaScript Function node
allRemove or restrict access to the vulnerable node in Flowise configurations.
🧯 If You Can't Patch
- Rotate all exposed secrets (API keys, cloud credentials, tokens) immediately.
- Monitor for unauthorized access to external services linked to Flowise environment variables.
🔍 How to Verify
Check if Vulnerable:
Check if using Flowise Cloud free tier before August 2025. Review tenant isolation in Custom JavaScript Function node.Check Version:
Check Flowise Cloud dashboard or contact Flowise support for version confirmation.Verify Fix Applied:
Confirm Cloud-Hosted Flowise version is August 2025 or later. Test tenant isolation by attempting to access other tenants' environment variables.📡 Detection & Monitoring
Log Indicators:
- Unusual access patterns to environment variables via JavaScript nodes
- Cross-tenant data access attempts
Network Indicators:
- Unexpected outbound connections to external APIs using stolen credentials
SIEM Query:
source="flowise" AND (event="environment_variable_access" OR event="javascript_node_execution")