Microsoft Excel CVE-2011-0103 Memory Corruption Vulnerability

Description

Microsoft Excel is prone to a memory-corruption vulnerability. Attackers can exploit this issue by enticing an unsuspecting user to open a specially crafted Excel file. Successful exploits can allow attackers to execute arbitrary code with the privileges of the user running the application. Failed exploit attempts will result in a denial-of-service condition.

Technologies Affected

• Microsoft Excel 2002
• Microsoft Excel 2002 SP1
• Microsoft Excel 2002 SP2
• Microsoft Excel 2002 SP3
• Microsoft Excel 2003
• Microsoft Excel 2003 Gold
• Microsoft Excel 2003 SP1
• Microsoft Excel 2003 SP2
• Microsoft Excel 2003 SP3
• Microsoft Office 2004 for Mac
• Microsoft Office 2008 for Mac
• Microsoft Open XML File Format Converter for Mac

Recommendations

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.

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.
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 exploits of memory-corruption vulnerabilities.

The vendor has released an advisory and updates. Please see the references for details.