Amiga Virus Encyclopedia
Zenker Bootblock Virus:
This virus is a new type of virus. It only uses a loaderroutine in
the ordinary bootsectors and all the virusparts are put in the sec.
from 896-898. The original BB will be written to the sectors 898-
900. That means that the sectordata 896-900 will be destroyed 100%
and cannot be fixed. What happens, if the headerblocks and other
structures are in this sectors ? You can forget this files. VW
offers you the possibility to rewrite the BB from 898 to sector 0.
In some cases this might work(for games with bootloaders ect.) but
in the most cases your disc is damaged and not useable anymore.
It can happen that the RDB block from your harddisc becomes over-
written. In this case it is too late. You can only restore the
backup of your RDB sectors (you surely have one!) and hope that
the information on sector 896-900 were not too important.
The virus uses some memory without allocating it.It uses $7f500
without allocating this memory space.
Detection tested on 23.3.93.
Block-0 tested on 23.3.93.
The Virus tries to look like a normal bootblockloader with the
string "COMMODORE Bootblockloader ....)....
Comment 28.11.1993: It appeared a Zenker Clone called INGO. Only
the visible texts were changed.
In the bootblock you can read now:
"Bootloader by Ingo(16 Feb.1993)
In the block 897 you can read:
"Now I am the 29 Generation"
In Block 989 you can read at 0-11 "== INGO!! ==".
Detection tested on 28.11.93.
Block-0 tested on 28.11.93.
Test by Markus Schmall