$ sqlplus / as sysdba
SQL*Plus: Release 19.0.0.0.0 - Production on Tue May 25 12:59:54 2021
Version 19.11.0.0.0
Copyright (c) 1982, 2020, Oracle. All rights reserved.
ERROR:
ORA-17500: ODM err:ODM ERROR V-41-4-1-83-9 Bad file descriptor
ORA-17500: ODM err:ODM ERROR V-41-4-1-83-9 Bad file descriptor
This issue is caused by currently unpublished Oracle BUG 32965460. See Oracle Doc ID 2792145.1.
Contact Oracle for patch 32965460.
Workaround: Connect with the sys user and password instead.
As of writing, it is also believed that this effects 19.12 and a patch will be released by Oracle in due course.