Search notes:

$ORACLE_HOME/bin/oradism

$ORACLE_HOME/bin/oradism has the setuid bit set: 
$ stat --format=%A $ORACLE_HOME/bin/oradism
-rwsr-x---
The setuid bit set because it was originally used to enable Dynamic Intimate Shared Memory (DISM).
In later releases, oradism was then additionally used to for other operations, mostly at database startup.
Additionally, oradism is owned by root: 
$ stat --format='%U %G' $ORACLE_HOME/bin/oradism
root oinstall
The owner and file permission of oradism is set by the shell script $ORACLE_HOME/rdbms/install/rootadd_rdbms.sh.

See also

$ORACLE_HOME/bin
MOS Note 1599721.1
Do not confuse oradism with Dism.exe which is a Deployment Image Servicing Utility for Windows.

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