RCE in Flowiseai Flowise

CVE-2026-70477

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.

Vulnerability class: RCE (Remote Code Execution)

EPSS: 0.008 (56.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-70477?
CVE-2026-70477 is a critical-severity vulnerability in Flowiseai Flowise, classified under Code Injection. CVSS score: 9.8/10. Published 2026-08-04.
How severe is CVE-2026-70477?
Critical severity. CVSS v3 base score is 9.8 out of 10.