CVE-2026-19306: CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') in IBM Langflow OSS

CVE-2026-19306 is a CWE-22 path traversal vulnerability in IBM Langflow OSS versions 1.0.0 through 1.11.2. An authenticated attacker can supply absolute or traversal paths in the files parameter of a build request to read arbitrary files from the server filesystem. This bypasses the LANGFLOW_RESTRICT_LOCAL_FILE_ACCESS=true restriction that is enforced on other file-reading components but not on the Chat Input to Message attachment pipeline. As a result, sensitive server files including secret keys, JWT signing keys, application databases, and other tenants' upload directories can be exfiltrated by embedding their contents in language model prompts sent to the configured model endpoint.

An attacker with authentication privileges can read highly sensitive files from the server, including secret keys and application databases, potentially compromising confidentiality of the system and other tenants. The vulnerability allows confidential data exfiltration without impacting system integrity or availability. This poses a significant risk to data confidentiality and multi-tenant isolation.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or temporary mitigation has been documented at this time. Until a patch is available, restrict authenticated user access to trusted parties only and monitor for suspicious file access patterns related to the files parameter in build requests.