Blocking of zip files in the email

A new attack method has been discovered in Microsoft Exchange, which could lead to a risk of ransomware (malware).

Several organizations in Sweden have been affected. We now need to be extra vigilant on emails. These can be replies to an existing email thread, emails that look different in some way or contain some form of attachment. So far, zip files have been used as an approach. CERT-SE recommends blocking zip files centrally in the spam filter, which has now been done at Linnaeus University.

How does this affect me?
This means that attached zip files in emails that are sent or received externally are stopped centrally in Lnu's spam filter. Internal emails are not affected. The person who sends the email receives a message back that it can not be delivered.

How can I share my files instead of sending zip files?
We recommend using either Box or OneDrive to share the files. It is possible to share both internally and externally.
In the Service Portal, you can read more about the options available.

CERT-SE is Sweden's national Computer Emergency Response Team with the task of supporting society in the work of managing and preventing IT incidents.
Read more about the attack method at CERT-SE (swedish).