Why it's impossible to install a package from the higher OS release?

I'm trying to install zip package on the server with "Red Hat Enterprise Linux Server release 7.4 (Maipo)" from the source dvd of "Red Hat Enterprise Linux Server release 7.5 (Maipo)" but the package installation fails.

Eg,

# By yum

[root@tst Packages]# cat /etc/yum.repos.d/iso.repo
[ISO_REPOSITORY]
name=RHEL 7.5
baseurl=file:///mnt
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release
gpgcheck=1
enabled=1

[root@tst Packages]# pwd
/mnt/Packages
[root@tst Packages]# ls -l zip*
-r--r--r--. 2484 root root 266180 May 3 2016 zip-3.0-11.el7.x86_64.rpm

[root@tst Packages]# yum install zip
...
Resolving Dependencies
--> Running transaction check
---> Package zip.x86_64 0:3.0-11.el7 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

================================================================================

Package Arch Version Repository Size

Installing:
zip x86_64 3.0-11.el7 ISO_REPOSITORY 260 k

Transaction Summary

Install 1 Package

Total download size: 260 k
Installed size: 796 k
Is this ok [y/d/N]: y
Downloading packages:

Error downloading packages:
zip-3.0-11.el7.x86_64: [Errno 256] No more mirrors to try.

# By the full name

[root@tst Packages]# yum install zip-3.0-11.el7.x86_64.rpm
...
Cannot open: zip-3.0-11.el7.x86_64.rpm. Skipping.
Error: Nothing to do

# By rpm

[root@tst Packages]# rpm -ivh zip-3.0-11.el7.x86_64.rpm
error: zip-3.0-11.el7.x86_64.rpm: not an rpm package (or package manifest):

# Added later.

As stated below, the issue has been fixed by the Virtual Machine reboot. I suppose something went wrong with the attaching of the disk to the VM.