what are the scenarios oracle database will become hung state?

what are the scenarios oracle database will become hung/crash state?
oracle database will become to hung/crashed status due to various reasons,Please find here.

1)when the archive file system 100% utilized.
2)When the oracle binary file system 100 % utilized
3)when the redo files corrupted
4)When the RAC nodes not able to communicate from private IP's
5) Dataguard Db down ,when the primary  DB in MAX protection mode.
6)when the SYSTEM related TBS running out of space
7)when the network failure on server

ORA-00700: soft internal error, arguments: [kskvmstatact: excessive swapping observed], [], [], [], [], [], [], [], [], [], [], []

issue:

ORA-00700: soft internal error, arguments: [kskvmstatact: excessive swapping observed], [], [], [], [], [], [], [], [], [], [], []

Description:

we recently got this error on 12c  database and it generated lot of trc file to incident directory and checked with oracle and they confirmed it's normal behavior of 12c database and its not a bug.

Given both the alert log message and ORA-700 are expected behavior for 12c, no action is required.