Sunday

Sunday is a computer virus (program file virus), a member of the Jerusalem virus family. It was discovered in November 1989 after a number of simultaneous reports from Seattle, Washington, United States, and surrounding areas. Several other Seattle outbreaks, including AirCop, were later traced to Asia. Infection Sunday is a standard patched Jerusalem variant in the way it infects files. It is a type of program file virus. It is a directly modified version of the original Jerusalem.1803. It infects .EXE, .COM, and files. Like the original Jerusalem, infected files occasionally become corrupted. Symptoms Sunday is less easily identified than the original Jerusalem, in part because of corrected errors and in part because its payload is poorly written and fails to execute. COM and EXE files increase by size. COM files increase by a set amount, while EXE files increase by somewhere between that amount and 9 or 10 bytes less. Unlike the original Jerusalem, files will not be infected many times. Interrupt 21 will be hooked. Infected files will contain the string "Today is SunDay! Why do you work so hard? All work and no play make you a dull boy! Come on! Let's go out and have some fun!"