Summary
CVE-2026-69255 is a code injection (CWE-94) vulnerability in the CSV Agent component of Flowise, the open-source low-code platform for building LLM applications and AI agents. Attacker-controlled CSV data is unsafely interpolated into Python code executed via Pyodide, allowing arbitrary operating system command execution. It affects Flowise versions prior to 3.1.3 and is rated Critical (CVSS 9.2).
Technical details
- Root cause: The CSV Agent extracts base64-encoded CSV data from a data URI and interpolates it directly into a generated Python code block as
base64_string = "${base64String}"before Pyodide execution. - Trigger conditions: An attacker crafts a base64 payload containing a closing quote followed by arbitrary Python, breaking out of the string context. The existing
validatePythonCodeForDataFrame()denylist only validates LLM-generated code, not this initial interpolated block, so the injected code is not filtered. - Attack vector: Network. The vulnerable code path is reached by submitting malicious CSV input to the CSV Agent.
- Impact: Execution of arbitrary OS commands, enabling full remote code execution, credential/environment-variable theft, unauthorized file access, and denial of service.
Affected software
- Flowise versions before 3.1.3 (i.e., ≤ 3.1.2).
Severity
- CVSS 9.2 (Critical).
- Vector:
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N.
Mitigation and recommended actions
- Immediate: Upgrade to Flowise 3.1.3 or later, which fixes the unsafe interpolation.
- If no patch can be applied: Restrict network access to the Flowise instance, avoid exposing it directly to the internet, enforce authentication and access controls, and avoid using the CSV Agent with untrusted input until upgraded.
How IONIX identifies potentially affected assets
IONIX matches the following signals against data already collected when it crawled the asset; identifying the technology sends no request beyond that crawl.
- Page title:
Flowise - Build AI Agents, Visually,Flowise - Low-code LLM apps builder - Raw response body:
data-rewardful="9a3a26",og:site_name…flowiseai.com authormeta tag content:FlowiseAIdescriptionmeta tag content:Open source generative AI development platform for building AI agents

