[Errno 14] curl#60 - "Peer's certificate issuer has been marked as not trusted by the user."

Issue

• yum transactions fail with [Errno 14] curl#60 - "Peer's certificate issuer has been marked as not trusted by the user."

• When creating a custom ISO image based on current release getting the following error:

  ...
  self.repos.populateSack(which=repos)
  File "/usr/lib/python2.7/site-packages/yum/repos.py", line 347, in populateSack
  self.doSetup()
  File "/usr/lib/python2.7/site-packages/yum/repos.py", line 157, in doSetup
  self.retrieveAllMD()
  File "/usr/lib/python2.7/site-packages/yum/repos.py", line 88, in retrieveAllMD
  dl = repo._async and repo._commonLoadRepoXML(repo)
  File "/usr/lib/python2.7/site-packages/yum/yumRepo.py", line 1470, in _commonLoadRepoXML
  result = self._getFileRepoXML(local, text)
  File "/usr/lib/python2.7/site-packages/yum/yumRepo.py", line 1248, in _getFileRepoXML
  size=102400) # setting max size as 100K
  File "/usr/lib/python2.7/site-packages/yum/yumRepo.py", line 1037, in _getFile
  raise e
  yum.Errors.NoMoreMirrorsRepoError: failure: repodata/repomd.xml from lorax-repo: [Errno 256] No more mirrors to try.
  https://cdn.redhat.com/content/dist/rhel/server/7/3/x86_64/os/repodata/repomd.xml: [Errno 14] curl#60 - "Peer's 
  certificate issuer has been marked as not trusted by the user."