We lack an entity check in the _vuser space filter cause the checks had been introduced in the commit af35de9, but only for spaces, functions and sequences. So when we've introduced user and role entity accesses in c46702f the filter had not been updated.

The side effect is the following code failing.

box.cfg{}
box.schema.user.create('password_updater')
box.schema.user.create('to_update_password_of')
box.schema.user.grant('password_updater', 'write', 'space', '_user')
box.schema.user.grant('password_updater', 'alter', 'user')
box.session.su('password_updater', box.schema.user.passwd, 'to_update_password_of', '1234')

Expected a successful exit, but the following error received:

2025-11-30 13:45:56.150 [22189] main [C]:-1 E> User 'to_drop' is not found {"type":"ClientError","code":45,"name":"NO_SUCH_USER","user":"to_drop","trace":[{"file":"[C]","line":4294967295}]}
2025-11-30 13:45:56.150 [22189] main say.c:85 F> fatal error, exiting the event loop