What’s Vulnerable › Vulnerabilities
CVE-2026-9138: Langflow is vulnerable to arbitrary file write and arbitrary file deletion due to unvalidated paths in file-processing components
- Severity: medium (CVSS 6.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.5% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-09-04 · updated 2026-09-10
- Weakness: CWE-22
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.
Affected products
- IBM Langflow OSS: from 1.0.0 before 1.11.3 — fixed in 1.11.3
How to fix
Upgrade to a fixed version: IBM Langflow OSS 1.11.3. Check the vendor advisory for mitigations.
References
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