What’s Vulnerable › Vulnerabilities

CVE-2026-33017: Langflow Code Injection Vulnerability

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: yes — in CISA KEV since 2026-03-25
• EPSS: 96.2% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-03-20 · updated 2026-06-17
• Weakness: CWE-94

Description

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/code by adding authentication. The build_public_tmp endpoint is designed to be unauthenticated (for public flows) but incorrectly accepts attacker-supplied flow data containing arbitrary executable code. This issue has been fixed in version 1.9.0.

Affected products

• IBM Langflow OSS: before 1.8.2 — fixed in 1.8.2

How to fix

Upgrade to a fixed version: IBM Langflow OSS 1.8.2. Check the vendor advisory for mitigations.

References

• https://github.com/advisories/GHSA-rvqx-wpfh-mfx7
• https://github.com/langflow-ai/langflow/commit/73b6612e3ef25fdae0a752d75b0fabd47328d4f0
• https://github.com/langflow-ai/langflow/security/advisories/GHSA-vwmf-pq79-vjvx
• https://github.com/langflow-ai/langflow/releases/tag/1.8.2
• https://medium.com/@aviral23/cve-2026-33017-how-i-found-an-unauthenticated-rce-in-langflow-by-reading-the-code-they-already-dc96cdce5896
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-33017
• https://www.sysdig.com/blog/cve-2026-33017-how-attackers-compromised-langflow-ai-pipelines-in-20-hours

Get alerted when CVE-2026-33017 or the next vulnerability affects your stack