You never know where the *malwares* are from.
"Be careful while downloading files. You never know where the malwares are from."
Is the use of "malwares" correct? Dictionaries say "malware" is an uncountable noun. Does it mean different kinds of malware, so it takes a plural form? Thanks!

Question

Answer

The use of malwares is incorrect. The plural/singular form of malware is just malware.

Edit: Actually with uncountable nouns there generally is no plural/singular form I think. Uncountable nouns are generally always referred to as if they are singular.