Hi mates,
There a problem when you try to upload a PDF v1.7 in CMDB. I work with Alfresco, but it is a Problem only from CMDBuild, i think.
My CMDB Version: 3.3.2
Alfresco Version: 7 (for make working Alfesco 7 in CMDBbuild 3.3.2 show: CMDBuild 3.3 Alfresco supported version - #9 by ecorona21 )
That Problem is because Tomcat version 9.0.31 (Default in CMDBbuild 3.3.2).
You only have to update Tomcat to version 9.0.41, (search a tutorial in internet, it´s really easy)
Only make a copy from conf/server.xml file to conf/server.xml_orig for example.
Download and extract Tomcat version 9.0.41 in a temporal dir.
stop CMDBuild
Copy all from temp dir to CMDBBuild dir.
And copy backup file form conf/server.xml_orig to conf/server.xml
start CMDBuild
good luck.