The report was released on Sunday by a group of 17 prominent media and rights groups. They found that Pegasus, developed by Israel's NSO Group, had been used by government-linked clients to hack at least 50,000 phone numbers in various countries, including in France.
"These are absolutely shocking facts which, if they are proven, are extremely serious," Attal told the France Info broadcaster, which is one of the media partners in the investigation.
He said the French government will conduct its own checks and request explanations.
At least 1,000 French nationals, including journalists from leading news outlets, have been targeted by Pegasus cyber-espionage, though the client was not France but Morocco, the broadcaster said, citing the results of the media investigation.
The Moroccan embassy in France reportedly dismissed the allegations when contacted by the broadcaster.