software vs malware

software and malware both are nouns.

Word	Noun	Adjective	Verb	Adverb
software	Yes	No	No	No
malware	Yes	No	No	No

As nouns, malware is a hyponym of software; that is, malware is a word with a more specific, narrower meaning than software:

software: (computer science) written programs or procedures or rules and associated documentation pertaining to the operation of a computer system and that are stored in read/write memory
malware: malicious software, designed to break into a system

software (noun)	malware (noun)
(computer science) written programs or procedures or rules and associated documentation pertaining to the operation of a computer system and that are stored in read/write memory	malicious software, designed to break into a system