Red Bull closed to within nine points of Ferrari's second place in the constructors' championship as Max Verstappen and Daniel Ricciardo finished third and fourth, while Kimi Raikkonen and Vettel were back in fifth and ninth.
Vettel put Ferrari's low-key weekend due to the car not gelling with the windy and sometimes cold and wet conditions at Silverstone.
"It has been a weak race for us," he admitted. "I don't think we need to turn the world upside down.
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"Today we seemed to lose a little bit compared to the people ahead.
"We recovered in qualifying but lost quite a lot of performance in the race with the conditions we faced, so there's a lot of stuff to understand."
He insisted the Silverstone result was an anomaly generated by a strong circuit for Red Bull coinciding with conditions in which Ferrari currently struggles.
"It was arguably a strong weekend for them and not a strong weekend for us," said Vettel.
"It's probably the only race this year where in terms of race pace we weren't able to fight with and beat them.
"I'm pretty confident things will look different again in two weeks.
"That's not an excuse, we had a bad weekend and we need to be sure we address this and take action and move forward and understand why we struggle more than other people.
"This weekend was a step back for us in terms of competitiveness, not necessarily a step up for other people."
Vettel also admitted he was concerned about the pair of gearbox failures on his car in practice, which resulted in the penalty that left him 11th on the grid.
His team-mate Raikkonen reckoned Ferrari's issue was a fundamental lack of downforce that proved particularly costly at a fast track with inclement weather.
"We are missing downforce and at a place like this it's not easy because of that," he said.
"You need downforce to go fast and especially with mixed conditions you take a big penalty on that.
"I'm sure the next circuits are much more normal for us than this place.
"But downforce would help any place, it doesn't matter where we go.
"If we had downforce like the cars in front of us it would be a different story."
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