07c3e67a71
* fix(security): prevent arbitrary file read via public flow build endpoint (GHSA-rcjh-r59h-gq37)
The unauthenticated `POST /api/v1/build_public_tmp/{flow_id}/flow`
endpoint accepted a `files` array whose paths were resolved by
`LocalStorageService` and read off disk before being attached to the
LLM prompt. A path like `/etc/hosts` was split into `flow_id="/etc"`
and `file_name="hosts"`. `data_dir / "/etc"` collapsed to `/etc`
because joining an absolute segment resets the prefix, and the
containment check was anchored at that attacker-controlled folder
so it passed. The file contents were then echoed back through the
chat reply.
Fix layers:
1. Boundary validation in `build_public_tmp`: each `files` entry
must match `{source_flow_id}/{basename}` with no traversal,
backslash, or null bytes. Foreign flow_ids are rejected with
HTTP 400.
2. `LocalStorageService._validated_path` now also rejects
`flow_id` values containing path separators, traversal, or
null bytes, and anchors the containment check at the data
directory rather than the per-flow folder.
Adds regression tests for both layers covering `/etc/hosts`,
traversal, foreign-namespace and null-byte payloads, plus an
acceptance test that legitimate `{flow_id}/{filename}` references
still work for AUTO_LOGIN playground uploads.
* add identifier validation
---------
Co-authored-by: cristhianzl <cristhian.lousa@gmail.com>
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