This is harmless memory resident parasitic virus. It hooks INT 21h and writes itself at the end of COM and EXE files (except COMMAND.COM) and AIDSTEST.EXE.
It's the polymorphic virus. It infects the files are executed or renamed. It cures infected files on their debugging or opening. It contains the internal text "ADIN" also, this is the name of the file which will be corrupted on accessing.
