A server‑side request forgery flaw exists in Flowise’s API Chain components, allowing attackers to inject malicious prompt templates that coerce the server into making arbitrary HTTP requests. By overriding the intended API documentation constraints, an attacker can target internal or external services, enabling network reconnaissance and data exfiltration. This specific weakness is mapped to CWE‑918.

The vulnerability affects FlowiseAI’s Flowise application and its flowise‑components package in any version prior to 3.1.0, regardless of deployment environment. The issue is present in both the drag‑and‑drop UI and the underlying REST endpoints used to create and execute API chains.

With a CVSS score of 8.3 and an EPSS indication of less than 1%, the risk of exploitation is considered moderate in terms of likelihood but high in potential impact. The vulnerability is not listed in the CISA KEV catalog. Attackers, who do not require authentication, can trigger the flaw by sending crafted GET or POST requests to the API Chain endpoints. The SSRF mechanism allows easy redirection to internal system addresses, providing a straightforward path to sensitive network discovery or data leakage.