CVE-2026-51888: Improper Limitation of a Pathname to a Restricted Directory

langflow-ai langflow v1.8.4 is affected by: Directory Traversal. The impact is: Arbitrary file write outside the intended workspace or storage boundary.. The component is: src/backend/base/langflow/api/v1/knowledge_bases.py:knowledge_bases-create_knowledge_base-a-live-http-post-to-create-knowledge-base. The attack vector is: Attack surface: HTTP or browser-backed service path. A public-facing upload or HTTP route handler forwards an attacker-controlled path or filename into host file creation without any visible boundary enforcement. ¶¶ A weakness has been identified in langflow-ai langflow up to 1.8.4. langflow contains an absolute path traversal vulnerability in knowledge_bases-create_knowledge_base-a-live-http-post-to-create-knowledge-base (src/backend/base/langflow/api/v1/knowledge_bases.py:51). An attacker can write or overwrite files outside the intended working directory by providing absolute paths in the knowledge base creation endpoint.