Hi morenpe,
Click on "About" in the bottom left of the menu bar. It will then display the patch version of the system.
GSB 160 - is the latest version for 4.3. This last patch contains the fix for ShellShock. There should be another patch being released soon for the GHOST exploit - CVE-2015-0235 aka "GHOST" glibc gethostbyname buffer overflow vulnerability
Refer to: How to download and patch the 4.3 Cloud Service Appliance Manually for the patch version codes and how to manually update the system.
I would highly recommended patching your system via the manual method above and then opening a support ticket to try to get the download patch content issue resolved. It may be that you do not have port 80 open in your firewall settings.
Hope this helps,
Peter