CVEs / CVE-2026-33017
CVE-2026-33017: Langflow Code Injection Vulnerability
- Known exploited in the CISA KEV catalog since 25 Mar 2026
- critical 9.8 CVSS 3.1 (NVD)
- EPSS 96.1% chance of exploitation in the next 30 days, higher than 99% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
Langflow contains a code injection vulnerability that could allow building public flows without requiring authentication.
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 and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| langflow-ai langflow | < 1.9.0 | — |
| Product | Affected | Fixed in |
|---|---|---|
| langflow (PyPI) | before 1.9.0 | 1.9.0 |
| langflow (PyPI) | before 1.3.0 | 1.3.0 |
| langflow-base (PyPI) | before 0.3.0 | 0.3.0 |
Package versions from GHSA-vwmf-pq79-vjvx, GHSA-rvqx-wpfh-mfx7.
Exploitation
| In CISA KEV since | 25 Mar 2026 |
|---|---|
| Due date for US federal agencies | 8 Apr 2026 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. |
Severity
| CVSS 3.1 | 9.8 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HScored by NVD |
|---|---|
| Weakness | CWE-94, CWE-95, CWE-306 |
References
- CVE-2026-33017 on NVD
- CVE-2026-33017 in the CISA KEV catalog
- https://github.com/langflow-ai/langflow/security/advisories/GHSA-vwmf-pq79-vjvx (cited by CISA)
- CVE-2026-33017 on OSV
- https://github.com/advisories/GHSA-rvqx-wpfh-mfx7 Third Party Advisory
- https://github.com/langflow-ai/langflow/commit/73b6612e3ef25fdae0a752d75b0fabd47328d4f0 Patch
- https://github.com/langflow-ai/langflow/security/advisories/GHSA-vwmf-pq79-vjvx Exploit, Mitigation, Vendor Advisory
- https://github.com/langflow-ai/langflow/releases/tag/1.8.2 Release Notes
- https://medium.com/@aviral23/cve-2026-33017-how-i-found-an-unauthenticated-rce-in-langflow-by-reading-the-code-they-already-dc96cdce5896 Exploit, Third Party Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-33017 US Government Resource
- https://www.sysdig.com/blog/cve-2026-33017-how-attackers-compromised-langflow-ai-pipelines-in-20-hours Press/Media Coverage
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.