The BBC looked at the arrival papers of a man called M al Mahmod, who arrived at the Island of Leros on October 3, and discovered that the picture is identical to the photo released by the French police.
Mahmod entered the EU along with another attacker supposedly named Ahmad al Mohammad, whose Syrian passport was found near the site of the attack.
Mahmod left Leros accompanied by al Mohammad and other Syrian refugees.
Bilal Hadfi, 20, the first Stade de France suicide bomber to be identified, turned out to be a French national who had been living in Belgium.
Salah Abdeslam, who took part in a street shooting, supposedly managed to flee the scene and return to Belgium, despite being stopped by police three times. He is now on the run.
His brother, 31-year-old Brahim Abdelslam, died when he detonated a suicide vest next to the Comptoir Voltaire café.