Adding network calls to syscalls like exec() is utterly insane. This road can lead to bricked laptops where you can't run anything to fix it (imagine an unexpected network error that the code doesn't handle properly). And crackers will just use ways to overwrite running instruction text to avoid the exec().
The comments on the article are annoying: it good that there's a mini way to reproduce, but please, use some further debugging like tcpdump (it still exists on osx, right?). Last time I summarized osx debugging was https://www.slideshare.net/brendangregg/analyzing-os-x-syste...
I'd also stress test it: generate scripts in a loop that include random numbers and execute them.
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