langflow-ai/langflow · error · HTTPException

Knowledge base '{kb_name}' not found

Error message

Knowledge base '{kb_name}' not found

What it means

Error "Knowledge base '{kb_name}' not found" thrown in langflow-ai/langflow.

Source

Thrown at src/backend/base/langflow/api/v1/knowledge_bases.py:239

    Raises 403 if path traversal is detected (kb_name escapes the user directory).
    Raises 404 if the KB directory does not exist.
    """
    kb_root_path = KBStorageHelper.get_root_path()
    kb_user = owner_user.username
    kb_user_path = (kb_root_path / kb_user).resolve()
    kb_path = (kb_user_path / kb_name).resolve()

    # The username roots the KB directory, so a username containing path separators
    # or ".." (e.g. "../../etc") could make kb_user_path resolve outside kb_root_path
    # while kb_path stays "contained" within that escaped base — bypassing the kb_name
    # check below and enabling arbitrary-directory access/deletion. Check containment
    # against the real root first, then the user dir for kb_name, matching the list
    # endpoint's guard.
    _validate_kb_path_containment(kb_root_path.resolve(), kb_user_path, kb_name, kb_user)
    _validate_kb_path_containment(kb_user_path, kb_path, kb_name, kb_user)

    if not kb_path.exists() or not kb_path.is_dir():
        raise HTTPException(status_code=404, detail=f"Knowledge base '{kb_name}' not found")
    return kb_path


def _build_connector_ingest_dedupe_key(
    *,
    user_id: uuid.UUID,
    kb_name: str,
    source_type: str,
    source_config: dict[str, Any],
) -> str:
    """Build a stable idempotency key for a connector-driven ingestion job.

    The key is a SHA-256 hash of ``(user, kb, source_type, sorted_config)``
    so semantically-equivalent requests collapse to the same key regardless
    of JSON key ordering. Only the hash (not the config) goes on the
    ``job`` row, so no credentials leak through ``dedupe_key``.
    """
    canonical = json.dumps(

View on GitHub (pinned to 976ec789d2)

Solutions

1. Verify the knowledge base name; it may have been deleted or renamed.

When it happens

Trigger: Occurs when the named knowledge base does not exist for the current user.

Common situations: See trigger scenarios.

AI-assisted analysis of langflow-ai/langflow@976ec789d2 (2026-08-14). Data as JSON: /api/errors/a8a167a619c875e9. Report an issue: GitHub.