CVE-2026-33873: Langflow

Critical severity, CVSS 9.9. EPSS: 1.8% chance of exploitation in the next 30 days.

Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to version 1.9.0, the Agentic Assistant feature in Langflow executes LLM-generated Python code during its validation phase. Although this phase appears intended to validate generated component code, the implementation reaches dynamic execution sinks and instantiates the generated class server-side. In deployments where an attacker can access the Agentic Assistant feature and influence the model output, this can result in arbitrary server-side Python execution. Version 1.9.0 fixes the issue.

Affected products

• Langflow Langflow: before 1.9.0 (fixed in 1.9.0)

Published 2026-03-27. Last modified 2026-06-17.