The PT_NOTE to PT_LOAD conversion infection method
This method is extremely powerful and, although easily detectable, is also relatively easy to implement and provides reliable code insertion. The idea is to convert the PT_NOTE segment to the PT_LOAD type and move its position to go after all of the other segments. Of course, you could also just create an entirely new segment by creating a PT_LOAD phdr entry, but since a program will still execute without a PT_NOTE segment, you might as well convert it to PT_LOAD. I have not personally implemented this technique for a virus, but I have designed a feature in Quenya v0.1 that allows you to add a new segment. I also did an analysis of the Retaliation Linux virus authored by Jpanic, which uses this ...
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