Vulnerability Description
IBM Langflow OSS 1.0.0 through 1.11.2 Langflow could allow an authenticated attacker to write arbitrary files to the server due to improper input validation in the SaveToFileComponent. The application constructs local file paths using attacker‑controlled input without sufficient sanitization when handling requests to the /api/v1/run/{flow_id} endpoint. An attacker with low‑privileged authenticated access (such as a valid API key or user session) can supply crafted path values, including absolute paths or path traversal sequences, allowing arbitrary file writes to locations writable by the Langflow process. Successful exploitation may lead to unauthorized file creation or modification, potentially resulting in further compromise depending on the deployment environment.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Langflow | Langflow | >= 1.0.0, < 1.11.3 |
| Apple | Macos | - |
| Linux | Linux Kernel | - |
| Microsoft | Windows | - |
Related Weaknesses (CWE)
References
- https://www.ibm.com/support/pages/node/7285643PatchVendor Advisory
FAQ
What is CVE-2026-9138?
CVE-2026-9138 is a vulnerability with a CVSS score of 6.5 (MEDIUM). IBM Langflow OSS 1.0.0 through 1.11.2 Langflow could allow an authenticated attacker to write arbitrary files to the server due to improper input validation in the SaveToFileComponent. The application...
How severe is CVE-2026-9138?
CVE-2026-9138 has been rated MEDIUM with a CVSS base score of 6.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-9138?
Check the references section above for vendor advisories and patch information. Affected products include: Langflow Langflow, Apple Macos, Linux Linux Kernel, Microsoft Windows.