Cyberattack shut municipal services in Herselt, Belgium

The municipality of Herselt in the Belgian province of Antwerp discovered a cyberattack on the evening of Friday, March 31, 2023 and responded by taking its systems offline. Public services stayed shut for much of the following week while external specialists worked through the network.

The town hall, the public library, the OCMW social welfare office and the Mixx leisure centre all closed. Staff could not send or receive email, residents could not request or submit documents through the usual channels, and the Mixx reservation system was unavailable. Sports and meeting facilities at the leisure centre remained in use. The municipality published alternative phone numbers so residents could still reach services, and warned it could not guarantee normal operations would resume by the following Tuesday.

Officials said they had taken the most drastic option available, shutting everything down and disconnecting the internet connection, then restoring functions one at a time as each was verified. Mayor Peter Keymeulen said it did not appear that the attackers had obtained sensitive information, though the administration acknowledged it was still investigating which data might have been copied. No ransom demand was received.

An early theory that the municipality's security provider had been the way in was set aside. The administration said an external software supplier had been compromised and that this was how malicious code reached Herselt's servers. VRT NWS reported in May 2023 that recovery and additional security measures had cost the municipality at least 28,000 euros, which it intended to recover through insurance and by holding the vendor liable.