CVE-2026-70477: Flowise: CSV Agent Prompt Injection Remote Code Execution Vulnerability

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-04 · updated 2026-10-24
Weakness: CWE-94

Description

Flowise is a drag & drop user interface to build a customized large language model flow. Prior to 3.1.3, a prompt injection sent to a chatflow using a CSV Agent node can cause the LLM to respond with a malicious Python script that bypasses the blocklist validator and executes in an unsandboxed Pyodide environment. The specific flaw exists within the run method of the CSV_Agents class, where untrusted data is used to construct an LLM prompt and the resulting pythonCode is validated by validatePythonCodeForDataFrame before execution. An attacker can leverage this to execute arbitrary code in the context of the service account. This issue is fixed in 3.1.3.

Affected products

FlowiseAI Flowise: before 3.1.3 — fixed in 3.1.3

How to fix

Upgrade to a fixed version: FlowiseAI Flowise 3.1.3. Check the vendor advisory for mitigations.

References

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