The rules endpoints were one instance of a pattern repeated across every
SharedObject-backed app. Route the rest through the same helper.
DCA entries were the worst case and are strictly wider than the reported
rules bug: DCAEntry has an unscoped default manager, so filtering by
strategy__id alone reached entries on strategies the caller could not see
at all. No public or shared strategy was needed -- only a guessable
integer. strategy_entry_add/edit/delete now resolve through the parent
strategy with via="strategy".
Every SharedObject delete view carried an inverted condition:
if obj.owner != request.user and request.user in obj.shared_with.all():
obj.shared_with.remove(request.user)
else:
obj.delete()
An object its owner had made public matched neither branch's intent and
fell through to delete(), so any authenticated user could destroy it.
Confirmed reachable for accounts, account groups, categories, tags,
entities and DCA strategies. The owner now deletes, a shared user revokes
only their own access, and anyone else gets a 403.
The API viewsets had no object-level check at all. DjangoModelPermissions
gated them shut for ordinary users, who hold no model permissions, so this
was not reachable in a default install -- but the check belongs there
regardless, and a user granted change_account in the admin could write any
visible account. SharedObjectPermission adds it for the SharedObject
viewsets, leaving reads to SharedObjectManager.
account_toggle_untracked only flips the calling user's own row in the
untracked_by m2m, so it takes READ rather than EDIT.
Refs GHSA-83g9-vjqf-2j5q
Regression tests for GHSA-83g9-vjqf-2j5q, one per endpoint the advisory
named plus the delete and view paths found alongside them: a non-owner
gets 403 on every mutation of a public or shared rule, and the object is
asserted unchanged afterwards.
Also covers the parts that are easy to regress in the other direction:
shared users keep read access, a shared user deleting only revokes their
own access, unowned rules stay claimable, and children of invisible rules
answer 404 rather than 403.
SharedObjectPredicateParityTests asserts is_visible_to agrees with
SharedObjectManager across every owner/visibility/shared combination.
The manager builds a Q and the predicate tests an instance, so they
cannot share an implementation and can otherwise drift apart.
SharedObjectManager scopes querysets to what a user may see, which
includes other people's public and shared-with-them objects. Several
mutating rule endpoints treated that visibility as permission to write.
Generalise get_owned_object_or_403 into get_shared_object_or_error, which
takes an explicit access level instead of inferring one:
- READ requires the object to be visible; denial is 404 so the response
does not confirm that an id exists.
- EDIT requires ownership; denial is 403, but only after the visibility
check, so 403 never leaks the existence of an invisible object. This
matters for TransactionRuleAction, whose manager is unscoped.
The previous owner_path resolved to a User and discarded the object, so
it could not express visibility at all. via= now points at the governing
SharedObject and is resolved with a plain getattr, so an unresolvable
path raises instead of silently granting access.
is_visible_to/is_editable_by replace is_accessible_by, which was never
called and tested visibility == "shared", a value that does not exist in
Visibility.
Also fixes two further holes in the same module:
- transaction_rule_delete fell through to delete() whenever the caller
was not in shared_with, so any user could delete a public rule. Now
only the owner deletes; a shared user revokes their own access.
- transaction_rule_view was read-only but is now explicitly READ, so
rules shared with a user stay viewable.
The activate/deactivate control is hidden for rules the user does not
own, instead of rendering a button that always fails.
Refs GHSA-83g9-vjqf-2j5q
Herculino Trotta