Purpose of a malware attack
A “targeted” attack is created for a specific purpose against a specific target. Examples are the DarkHotel malware, designed to steal information such as authentication details from government officials, and Stuxnet, the gift that kept (keeps) giving.
“Mass campaigns” are the most common type of attacks. These intend to infect as many devices as possible and perform whatever it may - regardless of target. An example is Wannacry, a ransomware that used the Eternalblue exploit.
And this is where it gets blurry. Advanced Persistent Threats (APTs) like the Crouching Yeti could be considered a “mass campaign” and specifically targets:
Industrial/machinery
Manufacturing
Pharmaceutical
Construction
Education
Information technology
In geopolitical terms, it can be considered a “targeted” attack. And because there is a rather large scope of this variant of malware, it can also be considered as a “mass campaign” attack.