Take SARS-CoV-2. It is a small RNA program ~32kb that duplicates and optimizes itself by random search.
It managed to hijack more computing power than our best supercomputers have [0] and kill a lot of us in the process.
By my estimates just the process of copying all SARS-CoV-2 vrions in the world with reproduction rate of 1 takes at least 1 petaFLOPS and up to 100 exaFLOPS.
That's in the range of TOP500 supercomputers (1.3 petaFLOPS - 442 petaFLOPS) [1].
SARS-CoV-2 has certainly a lot of computing power and is still able to outsmart the whole human civilization. Is that a super-intelligence?
Imagine if we manage to create equally stupid program that will figure out how to hijack heat or electrical power of our civilization and feed it into its own growth.
Quite likely it would result in nuclear meltdowns all around the world.
Exponentially growing computational processes are dangerous no matter if they are intelligent or whether they even have any objectives besides just being.