CVE-2026-9138

Langflow is vulnerable to arbitrary file write and arbitrary file deletion due to unvalidated paths in file-processing components

Published Sep 4, 2026 CVSS 3.1 · 6.5 Medium EPSS < 1% KEV · Not listed
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.

Remediation

Vendor Solution

IBM strongly recommends addressing the vulnerability now by upgrading Langflow OSS to version 1.11.3 https://pypi.org/project/langflow/

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Apple
Apple macos
Langflow
Langflow langflow
Linux
Linux linux Kernel
Microsoft
Microsoft windows
CPEs cpe:2.3:a:langflow:langflow:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:macos:-:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:*
Vendors & Products Apple
Apple macos
Langflow
Langflow langflow
Linux
Linux linux Kernel
Microsoft
Microsoft windows
Type Values Removed Values Added
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.
Title Langflow is vulnerable to arbitrary file write and arbitrary file deletion due to unvalidated paths in file-processing components
First Time appeared Ibm
Ibm langflow Oss
Weaknesses CWE-22
CPEs cpe:2.3:a:ibm:langflow_oss:1.0.0:*:*:*:*:*:*:*
cpe:2.3:a:ibm:langflow_oss:1.11.2:*:*:*:*:*:*:*
Vendors & Products Ibm
Ibm langflow Oss
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
ibm
Published
Updated
Sep 10, 2026, 9:00 PM
Reserved
May 20, 2026, 6:55 PM
Status
Analyzed
Published
Sep 4, 2026, 3:17 PM
Modified
Sep 10, 2026, 9:17 PM