Microsoft Visio is prone to a remote code-execution vulnerability because it fails to adequately handle user-supplied data. Attackers can exploit this issue to execute arbitrary code in the context of the user running the application. Failed exploit attempts will result in a denial-of-service condition.
Run all software as a nonprivileged user with minimal access rights.
To reduce the impact of latent vulnerabilities, always run nonadministrative software as an unprivileged user with minimal access rights.
Do not accept or execute files from untrusted or unknown sources.
To reduce the likelihood of successful exploits, never handle files that originate from unfamiliar or untrusted sources.
Implement multiple redundant layers of security.
Since this issue may be leveraged to execute code, we recommend memory-protection schemes, such as nonexecutable stack/heap configurations and randomly mapped memory segments. This tactic may complicate exploit attempts of memory-corruption vulnerabilities.
The vendor has released an advisory and fixes. Please see the references for more information.