p PatchFirst

CVE-2026-70470

CVE-2026-70470 · Flowise: Pyodide validator Unicode homoglyph bypass leads to RCE

This page contains facts from public vulnerability sources. Check the original advisory before updating.

Flowise is a drag & drop user interface to build a customized large language model flow. Prior to 3.1.3, Flowise validatePythonCodeForDataFrame in packages/components/src/pythonCodeValidator.ts can be bypassed with Unicode homoglyph identifiers, allowing arbitrary Python execution inside Pyodide and full OS command execution on the Flowise host via Pyodide js module interop. The validator gates pyodide.runPythonAsync in packages/components/nodes/agents/CSVAgent/CSVAgent.ts and packages/components/nodes/agents/AirtableAgent/AirtableAgent.ts with an ASCII word-boundary blacklist. JavaScript regex word boundaries are ASCII-only, while Python 3 NFKC-normalizes identifiers at parse time, so homoglyph forms such as __cl𝐚ss__, __subcl𝐚sses__, __b𝐚se__, and __b𝐮iltins__ bypass the blacklist and are parsed as their ASCII equivalents. This issue is fixed in version 3.1.3.

CVSS 9.5 · Critical · EPSS 1.0% · Fix available

Published
Updated

Stack: node

Affected products and versions

  • flowise

    Versions
    • < 3.1.3: Affected

    No fix published

  • flowise npm

    Affected ranges
    • SEMVER: < 3.1.3

    Update to 3.1.3

  • flowise-components npm

    Affected ranges
    • SEMVER: < 3.1.3

    Update to 3.1.3

Original sources

Check your server →