Kerr, 30, and Bloom recently ended their three-year marriage and in a joint statement announced that it was an amicable decision. They have a two-year-old son Flynn.
Kerr is said to have spent time with Bieber, 19, at a party in New York nearly a year ago, reports dailymail.co.uk.
She was pictured snuggling up to the singer in an eye-popping gem-encrusted green corset after a Victoria's fashion show in 2012.
"Orlando heard that there had been some flirting going on and he wasn’t exactly thrilled about it," said a source.
"Miranda had always claimed that she was a fan of Justin’s music. She has taught her son how to say Bieber fever but it is supposed to have caused an issue," the source added.