Apparently, he is slightly injured. The center-left Le Monde writes:

The tension was also palpable before the start of the speech. Before taking the stage, as the candidate crossed the crowd, an individual rushed at him and grabbed him by the neck, before being quickly overpowered and then exfiltrated. The man was taken into custody for "assault", according to information from Le Monde. At the end of the evening, Eric Zemmour's team let it be known that the candidate would have been injured in this incident and would have been prescribed 9 days of ITT by a doctor.