While an infected application is run, ZUC will cause the mouse pointer move diagonally across the screen while the mouse button is pressed. When running some infected applications, certain Macintosh computers will experience abnormal delay and disk activity in addition to a change in the desktop pattern. The weird cursor behavior will appear within a few minutes of running the infected application (the application need not be run).
The virus will only work on System 4.1 and later with ROMs smaller than 512 kilobytes.
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