Hundreds of Belgian organizations are at security risk because they have not sufficiently updated their Microsoft Exchange software. 

There are four vulnerabilities that Microsoft has fixed in the April 2021 updates. Many organizations have not yet installed the patch and are at risk of falling victim to a cyber attack called ProxyShell. This is a cyber attack that combines multiple vulnerabilities in Microsoft Exchange. The attack was revealed at the BlackHat cybersecurity conference in early August. 

The Center for Cybersecurity Belgium has identified vulnerable Belgian organizations and has started notifying them. No Belgian casualties have been reported yet. 

The CCB has issued a notice on 10 August recommending that priority be given to installing updates on Exchange servers. 

Belgian victims can always report cyber incidents to CERT.be.

The Center for Cybersecurity Belgium is closely monitoring the situation.