Users with automatic updates enabled will likely already have this update.
The solution is to uninstall the update from the control panel (add/remove programs). If you have enabled automatic updates, this update will still attempted to be installed, so if you have an afflicted system, you will have to start to control which updates are installed and avoid installing this one until/unless Microsoft finds a resolution (as of February 13 that was still not the case).
A site providing early information about the problem:
http://windowsitpro.com/msrc/patch-tuesday-font-corruption-kb3013455
Microsoft's description of the security update:
https://support.microsoft.com/kb/3013455
One report indicated that only the Courier New font was impacted, but in fact, Arial and other fonts have also been impacted by this update. As of early morning on February 11, 2015, one of our users running Windows 2003 SP2 reported experiencing this issue. It did not make their system unusable, but it caused text to be significantly less readable (all characters lighter overall, each character with broken connecting lines and not evenly rounded). The same user had the problem recur 24 hours later because of having automatic updates enabled.
In a Terminal Services environment, users logging into an afflicted server via remote desktop (RDP) may experience the problem, whereas directly connected user clients that either do not have the update or are running a non-impacted operating system may not experience the issue.
You can determine what Windows updates may be installed on your system by clicking on Start and then choose Search. Search for Windows Update. When Windows Update is found, click on Stop. There is a WindowsUpdate.log file than can be browsed and towards the end might show:
WindowsUpdate.log example:
2015-02-10 15:13:46:843 828 3848 Agent * Title = Security Update for Windows Server 2003 (KB3013455)