The flaw resides in the Execute Flow node of Flowise, where the base URL field is not validated against internal addresses. By supplying an intranet URL, an attacker can trigger the application‑side HTTP request and receive responses from private resources, cloud metadata services, or other internal endpoints. The compromised confidentiality can expose configuration details, internal service listings, or sensitive data accessible through those endpoints, and may act as a foothold for further attacks.

Flowise Flowise products before version 3.1.0 are affected. If an environment is running an older release, it is vulnerable regardless of deployment platform.

The issue is rated CVSS 6, indicating moderate severity. No EPSS information is available, and the vulnerability is not listed in KEV. Likely the attacker must submit a crafted request to the Execute Flow node, which may be publicly accessible or require authentication. Once the request is accepted, the server performs an outbound HTTP call to the specified base URL with no additional verification, making it straightforward to enumerate or exfiltrate internal resources. The risk remains significant for environments with sensitive internal services exposed through this node.