"We are investigating," Pirelli chief Mario Isola said.
"The tyres will be sent to Milan and studied," he revealed, "and we also need to see more setup data by the teams."
One suggestion was that Ferrari's particular setup, combined with the high downforce produced by the 2017 car, at least contributed to the problems.
Ferrari boss Maurizio Arrivabene, however, made clear his feelings about the blame.
"Although the reasons to us are obvious, it is not Ferrari's style to complain about losing a second and fourth place," he is quoted by Bild newspaper.
But Vettel commented: "I don't think anyone is particularly to blame. With hindsight everything is easy."
As for his decimated championship lead, which now stands at just a single point over Lewis Hamilton, the German added: "There is no reason for panic or concern.
"The last races were not quite as good, but I think we cannot forget how far away we were last year.
"It is true that Mercedes was stronger in the last races, but I think the biggest problem for us is qualifying. At the same time we have a fast car and once we work on a few things, it could be a different picture again," said Vettel.