The ISERBA Group is a property maintenance firm (plumbing, heating, electricity, carpentry, etc.). An undated notice on their web site indicates that they have been the victim of a cyber attack.
Machine Translation:
Our IT services were hacked during the weekend.
For security reasons, we are not reachable at the moment and our accesses are cut. All our teams are mobilized to secure and restart all our information systems as soon as possible. We apologize for the inconvenience caused, and we thank you for your understanding of this exceptional situation. ISERBA
A notice by Logéal Immobilière on Facebook on May 10 indicates that the attack occurred on the preceding weekend:
There does not seem to be any other news coverage or updates since then, so it seems to be a serious attack.