A program has been discovered that infects a critical Windows system executable and stays dormant in memory. When a Windows mobile phone is connected to the host, the program infects the phone's boot loader and continues to target additional Windows PCs or phones. Which of the following malware categories BEST describes this program?
Answer Description
A virus is a type of malware that infects another program (typically an exe/executable) and has the ability to spread itself to other systems. Both viruses and worms may have the ability to replicate themselves with or without user intervention. They key difference is that a worm is a standalone program while a virus infects an existing program, for example a critical Windows executable.
Wikipedia
A computer virus is a type of malicious software program ("malware") that, when executed, replicates itself by modifying other computer programs and inserting its own code. Infected computer programs can include, as well, data files, or the "boot" sector of the hard drive. When this replication succeeds, the affected areas are then said to be "infected" with a computer virus.
Virus writers use social engineering deceptions and exploit detailed knowledge of security vulnerabilities to initially infect …
Computer virus - Wikipedia, the free encyclopedia