CVE-2026-70477
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.83%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 4.0
- 9.5 CRITICALCVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.83% probability · 56th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-94
- Affected
- flowiseai/flowise
- Source
- security-advisories@github.com
References
- https://github.com/FlowiseAI/Flowise/commit/f4e2794f6a576b94578f2fdafbf49c2fb304626cPatch
- https://github.com/FlowiseAI/Flowise/pull/6499Issue Tracking, Patch
- https://github.com/FlowiseAI/Flowise/releases/tag/flowise@3.1.3Release Notes
- https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-5xvg-pmgg-3mxrVendor Advisory
- https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-5xvg-pmgg-3mxrVendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.