GHSA-79ph-745m-6wxq: Langflow: Path Traversal in Knowledge Bases API via Creation Endpoint

Summary

Langflow's Knowledge Bases API, specifically the POST /api/v1/knowledge_bases endpoint, builds filesystem paths directly from the user-supplied name field without sanitization or containment checks. An authenticated attacker can use traversal sequences or absolute paths to create directories and write embedding_metadata.json and schema.json anywhere the application has write permissions, enabling cross-user data compromise, arbitrary directory creation, and overwriting of existing knowledge base files.

Mitigation

Fixed in PR #12337, which adds the _validate_kb_path_containment() helper using Path.is_relative_to() and applies it before any filesystem operations. Regression tests confirm traversal payloads return 403 Forbidden.

Affected packages in the Exposure Registry

Matched by package name and ecosystem. Each entry shows whether the package delegates to a language model and how many tracked packages depend on it.

• langflowPyPIReaches an LLM package through dependencies

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