Intrusion
Penetration
noun, verbal noun, の adjective
If you invade and enter that is an intrusion.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
このコンピュータウィルスは、大晦日の夜に時計の針が12時を告げると、何千台ものパソコンに侵入をするんですよ。
This computer virus is going to penetrate thousands of computers at the stroke of midnight on the night of New Year’s Eve.
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