Microsoft Office is prone to a remote code-execution vulnerability. This issue occurs when the application processes certain Office files. Note that this issue may not be exploited automatically through email. For an attack to succeed, a victim must manually open an attachment sent by email or obtained through other means. An attacker may exploit this issue to execute arbitrary code in the context of the currently logged-in user. This issue affects the Microsoft Office 2003 Brazilian Grammar Checker application used in various Microsoft applications that have Brazilian Portuguese language support.
Run all software as a nonprivileged user with minimal access rights.
Ensure that all non-administrative tasks are performed as an unprivileged user with minimal access rights.
Deploy network intrusion detection systems to monitor network traffic for malicious activity.
Deploy NIDS to monitor network traffic for signs of suspicious or anomalous activity. This may help detect malicious actions that an attacker may take after successfully exploiting vulnerabilities in applications. Review all applicable logs regularly.
Do not accept or execute files from untrusted or unknown sources.
Users should never accept files from untrusted or unknown sources, because they may be malicious in nature. Avoid opening email attachments from unknown or questionable sources.
Do not follow links provided by unknown or untrusted sources.
Users should avoid websites of questionable integrity. Never follow links supplied by unknown 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 non-executable stack/heap configurations and randomly mapped memory segments. This tactic may complicate exploits of memory-corruption vulnerabilities.
Microsoft has released a security advisory and fixes addressing this issue. Please see the reference section for more information.