An encrypted message from the number used by the de facto Saudi ruler included a malicious file that infiltrated Bezos’ phone, The Guardian reported.
It said digital forensic analysis that found it “highly probable” that the intrusion into the phone was triggered by a message sent from bin Salman’s account.
The pair had been having a conversation on Whatsapp on 1 May 2018 when the unsolicited file was sent, the report said, citing anonymous sources.
Large amounts of data were reportedly exported from Bezos’ phone within hours.
The Saudis had previously denied accessing Bezos’ phone.
Digital experts started examining the billionaire’s phone last January after nude photos of Bezos and racy messages were leaked to tabloid the National Enquirer.
The alleged hack occurred five months before the murder of Washington Post journalist Jamal Khashoggi who was killed after being lured to the Saudi embassy in Istanbul.
Bezos owns the Washington Post which often featured columns critical of the Saudi government by the exiled journalist.
The Central Intelligence Agency (CIA) of the US concluded that bin Salman ordered Khashoggi’s murder, but the Saudi government has blamed rogue elements.
In December a Saudi court sentenced five men to death and three men to jail for the murder, but exonerated the crown prince and his inner circle.
Amazon and the Saudi embassy in the UK were contacted for comment.