The spinoff endpoint authenticated the caller (_require_user) but never
verified the research session belonged to them before reading the
persisted report and seeding it into a new chat session owned by the
caller. Any authenticated user who knew or guessed another user's
research session ID could exfiltrate that user's full report into their
own session — a cross-user data disclosure (IDOR).
Every other endpoint in this router gates on _owns_in_memory /
_assert_owns_research right after validating the session ID; spinoff was
the lone exception. Add the same _owns_in_memory check (covers both the
in-memory task and the on-disk JSON) so a non-owner gets a 404 before any
data is read or a session is created.
Add regression tests pinning the anonymous (401) and wrong-owner (404)
cases.
Every research endpoint interpolates session_id into filesystem paths
(Path('data/deep_research') / f'{session_id}.json') without checking
for traversal sequences. A crafted ID like '../../data/auth' reaches
arbitrary JSON files — readable via research_detail (which also leaks
file paths in error messages), writable via research_archive, and
deletable via research_delete.
Add _validate_session_id() which rejects anything outside
[a-zA-Z0-9-]{1,128}. Called before filesystem access in all 12
endpoints that accept a session_id path parameter.