[{"_id":"fijo_1","Procesos":[{"code_a":"1234","code_b":"5678","code_c":"9012","vector_aux":["01","02"],"leido":false},{"code_a":"0000","code_b":"1111","code_c":"2222","vector_aux":["03","04"],"leido":false}]},{"_id":"fijo_2","Procesos":[{"code_a":"3333","code_b":"4444","code_c":"5555","vector_aux":["01","02"],"leido":false},{"code_a":"6666","code_b":"7777","code_c":"8888","vector_aux":["03","04"],"leido":false}]}]

db.collection.update({"_id":"fijo_2"},{$set:{"Procesos.$[element].leido":true}},{arrayFilters:[{"element.code_a":"3333","element.code_b":"4444","element.code_c":"5555",}],upsert:true})