- Critical 9.3
- Known exploited (CISA KEV)
CVE-2026-33017
Langflow is a tool for building and deploying AI-powered agents and workflows. In versions prior to 1.9.0, the POST /api/v1/build_public_tmp/{flow_id}/flow endpoint allows building public flows without requiring authentication. When the optional data parameter is supplied, the endpoint uses attacker-controlled flow data (containing arbitrary Python code in node definitions) instead of the stored flow data from the database. This code is passed to exec() with zero sandboxing, resulting in unauthenticated remote code execution. This is distinct from CVE-2025-3248, which fixed /api/v1/validate/c…
Scores
The facts
- Published
- 20 March 2026
- Last changed
- 17 June 2026
- NVD status
- Analyzed
- Severity
- Critical, CVSS 9.3 out of 10 (version 4.0)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R… - Weakness
- Affects
- langflow langflow
- Known exploited
- Yes. CISA added it to the Known Exploited Vulnerabilities catalogue on 25 March 2026.
- EPSS
- 24.8% chance of exploitation activity in the next 30 days (percentile 98).
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