The vulnerability exists in Flowise through version 3.1.4, where route‑level RBAC checks are missing on chat message endpoints. This flaw allows attackers who possess a valid, but low‑privileged API key to call GET and DELETE chat message routes without needing the proper flow permissions. As a result, the attacker can read existing chat histories, including prompts and model responses, and can delete messages or entire chat logs.

The affected systems are deployments of Flowise AI’s Flowise platform up to and including version 3.1.4. Any installation that supports chat message routes and relies on API keys for authentication is vulnerable. The vendor is FlowiseAI, product Flowise. No specific consumer platforms are listed, so all users of the platform until the release of v3.1.5 or later must consider this risk.

The CVSS v3.1 score of 7.5 indicates a high severity vulnerability. EPSS is not available, so the exploitation probability cannot be quantified, but the lack of protection on chat routes means any legitimate but low‑privileged API key can be abused, making the risk real. The vulnerability is not listed in CISA’s KEV catalog. Attackers require only possession of an API key; no additional privileges or network access are needed beyond those foreseen for legitimate use, making the likelihood of exploitation high in environments where API keys are weakly protected or widely distributed.