Sudo Su - with Error Su: Failed to Execute /Bin/Bash: Permission Denied

I have a Red Hat Enterprise Linux Server release 7.7. Local user created. Sudoers file configured with ALL = (ALL) ALL for the user. The user can execute any command, like: sudo ls, sudo cat, sudo wherever.

However, the following command does not work: sudo su - It receives error message:

Last login: Tue Jun 15 10:21:52 -03 2021 on pts/1
su: failed to execute /bin/bash: Permission denied

I've already checked files and directory permissions.

[root@hostname ~]$ ls -l /bin/bash
-rwxr-xr-x 1 root root 964592 Mar 12  2019 /bin/bash

[root@hostname ~]$ ls -ld /usr/lib*
drwxr-xr-x 40 root root 12288 Mar 26  2020 /usr/lib
drwxr-xr-x 59 root root 36864 May 11  2020 /usr/lib64
drwxr-xr-x 24 root root  4096 Mar 24  2020 /usr/libexec

[root@hostname ~]$ ls -ld /tmp/
drwxrwxrwt 75 root root 12288 Jun 15 09:34 /tmp/

[root@hostname ~]$ stat /
  File: ‘/’
  Size: 4096            Blocks: 8          IO Block: 4096   directory
Device: fd01h/64769d    Inode: 2           Links: 22
Access: (0755/drwxr-xr-x)  Uid: (    0/    root)   Gid: (    0/    root)
Access: 2021-06-15 09:30:45.000000000 -0300
Modify: 2020-03-27 17:56:07.000000000 -0300
Change: 2021-06-15 09:30:44.000000000 -0300
 Birth: -

Any ideas?