I checked the possibilities for the below error. As per my finding if you try to install files for greater version into a lower version of red-hat. 

On downloading the rpm file  (cloudera-cdh-5-0.x86_64.rpm) and using the command  yum --nogpgcheck localinstall cloudera-cdh-5-0.x86_64.rpm from root user , I get below error:


Running rpm_check_debug ERROR with rpm_check_debug vs depsolve: rpmlib(FileDigests) is needed by cloudera-cdh-5-0.x86_64 rpmlib(PayloadIsXz) is needed by cloudera-cdh-5-0.x86_64

Can you please try the steps again. Kindly use the below command:

1) Open Terminal and execute the below command:

2) Execute the below command:
sudo yum --nogpgcheck localinstall cloudera-cdh-5-0.x86_64.rpm
This should add the repository in your redhat 5 distribution. 
I have tried the same with CentOs 5, it worked fine. Please check the below screen-shot:

Please try this and let me know if this works for you or not. I will wait for your response.