

Zombies that stick around for more than a few seconds indicate a signal problem in the parent process, where its init is stuck in the “wait” state, so the entry remains in the PID table.
It could be harmless, but it could become a problem if you need the resources. Curl shouldn’t be doing this on its own.



Agreed, but a very poorly-written program having a hanging memory or disk write, or a file lock could become a problem, especially if hundreds or thousands of zombies are waiting for something.