Remote Code Execution Vulnerability: Microsoft CVE-2017-8570

Description:

A remote code execution vulnerability exists in Microsoft Office software when it fails to properly handle objects in memory. An attacker can leverage this issue to execute arbitrary code in the context of the currently logged-in user. Failed exploit attempts will likely result in denial of service conditions. It has been classified as critical. Affected is an unknown function of the component Object Handler. The manipulation with an unknown input leads to a privilege escalation vulnerability. CWE is classifying the issue as CWE-269. This is going to have an impact on confidentiality, integrity, and availability.

Overview of Attack:

An attacker who successfully exploited the vulnerability could use a specially crafted file to perform actions in the security context of the current user. For example, the file could then take actions on behalf of the logged-on user with the same permissions as the current user. Exploitation of this vulnerability requires that a user open a specially crafted file with an affected version of Microsoft Office software.

In an email attack scenario, an attacker could exploit the vulnerability by sending the specially crafted file to the user and convincing the user to open the file. In a web-based attack scenario, an attacker could host a website (or leverage a compromised website that accepts or hosts user-provided content) that contains a specially crafted file that is designed to exploit the vulnerability. However, an attacker would have no way to force the user to visit the website. Instead, an attacker would have to convince the user to click a link, typically by way of an enticement in an email or Instant Messenger message, and then convince the user to open the specially crafted file.

Technologies Affected:

• Microsoft Office 2007 Service Pack 3
• 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)

Recommendations:

1. Run all software as a non-privileged user with minimal access rights.
2. Deploy network intrusion detection systems to monitor network traffic for malicious activity.
3. Do not accept or execute files from untrusted or unknown sources.
4. Do not follow links provided by unknown or untrusted sources.
5. Implement multiple redundant layers of security.

References:

• CVE-2017-8570
• Microsoft - Microsoft Homepage
• Microsoft - Microsoft Office Product Homepage