Microsoft Excel CVE-2018-8502 Security Bypass Vulnerability

Description

Microsoft Excel is prone to a security-bypass vulnerability. An attacker can leverage this issue to bypass certain security restrictions and execute arbitrary code in the context of the affected application; this may aid in launching further attacks.

Technologies Affected

• Microsoft Excel 2010 Service Pack 2 (32-bit editions)
• Microsoft Excel 2010 Service Pack 2 (64-bit editions)
• Microsoft Excel 2013 RT Service Pack 1
• Microsoft Excel 2013 Service Pack 1 (32-bit editions)
• Microsoft Excel 2013 Service Pack 1 (64-bit editions)
• Microsoft Excel 2016 (32-bit editions)
• Microsoft Excel 2016 (64-bit editions)
• Microsoft Office 2010 Service Pack 2 (32-bit editions)
• Microsoft Office 2010 Service Pack 2 (64-bit editions)
• Microsoft Office 2013 RT Service Pack 1
• Microsoft Office 2013 Service Pack 1 (32-bit editions)
• Microsoft Office 2013 Service Pack 1 (64-bit editions)
• Microsoft Office 2016 (32-bit edition)
• Microsoft Office 2016 (64-bit edition)
• Microsoft Office 2019 for 32-bit editions
• Microsoft Office 2019 for 64-bit editions
• Microsoft Office 365 ProPlus for 32-bit Systems
• Microsoft Office 365 ProPlus for 64-bit Systems

Recommendations

Run all software as a nonprivileged user with minimal access rights.
To mitigate the impact of a successful exploit, run the affected application as a 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.
Never accept files from untrusted or unknown sources, because they may be malicious in nature. Avoid opening email attachments from unknown or questionable 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.

Updates are available. Please see the references or vendor advisory for more information.