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.
"}],"value":"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."}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":6.5,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"HIGH","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N","version":"3.1"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-22","description":"CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-09-04T14:27:27.568Z","orgId":"9a959283-ebb5-44b6-b705-dcc2bbced522","shortName":"ibm"},"references":[{"tags":["vendor-advisory","patch"],"url":"https://www.ibm.com/support/pages/node/7285643"}],"solutions":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"IBM strongly recommends addressing the vulnerability now by upgrading Langflow OSS to version 1.11.3
"}],"value":"IBM strongly recommends addressing the vulnerability now by upgrading Langflow OSS to version 1.11.3 https://pypi.org/project/langflow/"}],"title":"Langflow is vulnerable to arbitrary file write and arbitrary file deletion due to unvalidated paths in file-processing components"}},"cveMetadata":{"assignerOrgId":"9a959283-ebb5-44b6-b705-dcc2bbced522","assignerShortName":"ibm","cveId":"CVE-2026-9138","datePublished":"2026-09-04T14:27:27.568Z","dateReserved":"2026-05-20T18:55:09.275Z","dateUpdated":"2026-09-10T21:00:35.612Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-04 15:17:50","lastModifiedDate":"2026-09-10 21:17:53","problem_types":["CWE-22","CWE-22 CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')"],"metrics":{"cvssMetricV31":[{"source":"psirt@us.ibm.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N","baseScore":6.5,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"HIGH","availabilityImpact":"NONE"},"exploitabilityScore":2.8,"impactScore":3.6}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-09-10T20:38:48.950712Z","id":"CVE-2026-9138","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"configurations":[{"operator":"AND","nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:langflow:langflow:*:*:*:*:*:*:*:*","versionStartIncluding":"1.0.0","versionEndExcluding":"1.11.3","matchCriteriaId":"E7183EAA-D662-465F-8176-7CCC96E6E470"}]},{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":false,"criteria":"cpe:2.3:o:apple:macos:-:*:*:*:*:*:*:*","matchCriteriaId":"387021A0-AF36-463C-A605-32EA7DAC172E"},{"vulnerable":false,"criteria":"cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:*","matchCriteriaId":"703AF700-7A70-47E2-BC3A-7FD03B3CA9C1"},{"vulnerable":false,"criteria":"cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:*","matchCriteriaId":"A2572D17-1DE6-457B-99CC-64AFD54487EA"}]}]}]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"9138","Ordinal":"1","Title":"Langflow is vulnerable to arbitrary file write and arbitrary fil","CVE":"CVE-2026-9138","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"9138","Ordinal":"1","NoteData":"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.","Type":"Description","Title":"Langflow is vulnerable to arbitrary file write and arbitrary fil"}]}}}