The 29-year-old was man of the match in Saturday's seven-wicket rout of Pakistan.
Along with New Zealand pair Matt Henry and Mitchell Santner, he is the tournament's leading wicket-taker with eight in three games.
Bumrah's eight wickets have cost just 93 runs.
His performance in the 132,000-seater Ahmedabad Stadium on Saturday also saw him bring out his distinctive celebration -- pointing his right index finger to his temple.
It's a gesture used by England footballer Marcus Rashford, a player at Bumrah's favourite club Manchester United.
Three-time tennis Grand Slam title winner Stan Wawrinka also utilises it at key moments.
"I had no intentions of making it viral or spreading it everywhere," Bumrah told the ICC Digital Insider on Sunday.
"It just came to my mind. I'd seen Rashford do it as well. I thought it was cool. There's no particular big back story behind it. At the end I decided to do it.
"Usually I'm too tired to celebrate. But that is one occasion where I did celebrate."
Bumrah took two wickets in India's opening win of the World Cup against Australia and added four more in the win over Afghanistan.
On Saturday, he dismissed dangerman Mohammad Rizwan and then Shadab Khan before finishing the match with 2-19.
Despite a 100% record, India are not thinking yet of a third World Cup title to add to triumphs in 1983 and on home soil in 2011.
"We're not thinking about the momentum. The team is right now thinking about recovery," Bumrah said as India head for Pune and their fourth game against Bangladesh on Thursday.
"We've played three games back-to-back and the result has been on the good side because our preparation has been good.
"The team vibe is also good. People are pretty relaxed. They're looking to execute, they're looking to have fun with each other. It's a good place to be now."