It is a dangerous memory resident parasitic virus. It hooks INT 21h and writes itself to the end of .COM files that are executed. While infecting, the virus writes 16 bytes of code and data to the file beginning :
+-----------------------------------------------------
¦JMP Loc_Virus¦A T T E N T I O N !¦1Ah¦ file
+-----------------------------------------------------
3 bytes 12 bytes 1 byte
While infecting, the virus hooks INT 24h, but does not restore its original value - this might hang the system.
The virus manifests itself upon infecting files on a write-protected disk in the A: drive: the motor is switched on (regardless what disk is being accessed). In infected files starting from the 4th byte you can find the string
ATTENTION !
