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CVE-2026-9138

Status: AnalyzedMedium (6.5)—

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

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (1)

Langflow — Langflow

CWEs

References

Raw JSON (NVD)

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  "id": "CVE-2026-9138",
  "cveTags": [],
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          "options": [
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          "version": "2.0.3",
          "timestamp": "2026-09-10T20:38:48.950712Z"
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          "userInteraction": "NONE",
          "attackComplexity": "LOW",
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          "privilegesRequired": "LOW",
          "confidentialityImpact": "NONE"
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    }
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  "lastModified": "2026-09-10T21:17:53.760",
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