Ambiguous field exception in AR

test_case.rb

class Foo
  has_many :bazs
  has_many :bars, through: :bazs
end

class Baz
  belongs_to :foo
  has_many :bars
end

class Bar
  default_scope -> { order('created_at DESC') }
  belongs_to :baz
end

# 
foo.bars.update_all attribute: 'new_value'