Hackers tried on Tuesday evening to break into the system of the municipality of Zutphen, the municipality writes on the website. The municipality suspects that the hacking attempt is related to a vulnerability in the servers of the American supplier Citrix, the same vulnerability was probably also used in the hacking attempt on the servers of the Medical Center Leeuwarden (MCL).

It is not yet clear exactly what the consequences are of the hacking attempt, but the municipality does not write any signals that indicate that the hack was successful or that data were stolen.

The municipality shut down the municipality's systems on Tuesday evening when the hacking attempt was discovered. The municipality is currently investigating what exactly happened and what the consequences are.

The Leeuwarden Medical Center (MCL) also became the target of a hacking attempt on Tuesday evening. The cause was probably also the Citrix vulnerability. After the attack was discovered on Tuesday evening, the MCL cut off the internal network from the outside world

Hundreds of vulnerable servers in the Netherlands

It was announced on Sunday that at least 713 servers in the Netherlands are at risk due to a vulnerability in Citrix systems. The National Cyber ​​Security Center (NCSC) warned that the leak was being actively attacked.

Security researcher Matthijs Koot, who works at Secura and as a researcher at the University of Amsterdam, told NU.nl on Monday that hospitals, but also ministries and mental healthcare institutions are at risk. He called the vulnerability a "very big problem with great urgency".

Citrix expects to be able to offer an update on January 20 at the earliest that removes the vulnerability. For certain versions of the firmware (software programmed in hardware), an update may take a few days longer.