Langflow · Langflow
Langflow, the tool for building and deploying AI-powered agents and workflows, contains a code injection flaw in its POST /api/v1/build_public_tmp/{flow_id}/flow endpoint. An unauthenticated remote attacker over the network can supply flow data containing arbitrary Python code in a node definition via the optional data parameter, which the endpoint passes to exec() without sandboxing, requiring no authentication or user interaction.
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.
First seen exploited 1 day before it was disclosed. Public exploit code (Metasploit) was available the same day.
CISA KEV listing is when exploitation was confirmed, not necessarily the first attack.
2 related vulnerabilities in the same code over 11 months.
Why these are linked: Link confidenceHow strong the evidence is that two CVEs are related. High: stated in the CVE text or linked in an advisory, or the same code was patched one release apart. Medium: the same code, or a version step plus a similar description. Low: similar description only.
unauthenticated public-facing endpoint is the entry point
POST /api/v1/build_public_tmp/{flow_id}/flow endpoint allows building public flows without requiring authentication
attacker-supplied Python executed via exec()
This code is passed to exec() with zero sandboxing, resulting in unauthenticated remote code execution
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1 package in 1 ecosystem. Main package: langflow.
Upgrade to 1.10.3 or later
Fixes this CVE and 12 other known vulnerabilities in this package (CVE-2024-37014, CVE-2025-3248, +10).
pip install "langflow>=1.10.3"First fixed in 1.9.0 for CVE-2026-33017.
| If you run | Upgrade to |
|---|---|
| All versions before 1.9.0 | 1.10.3first fix for this CVE: 1.9.0 |
“Up to” means the second version is the fix and is not affected.
Pulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.