CVE-2026-9138 Path traversal in Langflow OSS
Authenticated attackers can write or delete arbitrary files via path traversal in Langflow, potentially leading to server compromise.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-9138?
CVE-2026-9138 is a medium-severity path traversal vulnerability in Langflow Langflow, published on 4 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official 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.
Weakness: CWE-22
Which versions are affected by CVE-2026-9138?
It affects 1 product.
Products include Langflow Langflow.
How do I fix CVE-2026-9138?
No fix has been published for CVE-2026-9138 yet. Limit exposure of the affected software until one is available.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-9138 being exploited?
There is no known exploitation of CVE-2026-9138 in the wild and no public exploit code.
Other vulnerabilities in Langflow Langflow
Sources
Also known as GHSA-44jp-wv2q-qjwp.