Medium severity · published Sep 4, 2026
CVE-2026-9138
Langflow is vulnerable to arbitrary file write and arbitrary file deletion due to unvalidated paths in file-processing components
6.5
CVSS
0.5%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 39% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LO
Langflow OSS · IBM
1.0.0 through 1.11.2 · source: vendor
LA
Langflow · Langflow
1.0.0 before 1.11.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-9138
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-9138
Patch
https://www.ibm.com/support/pages/node/7285643
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