CIS CYBER SECURITY ADVISORIES

MS-ISAC CYBER SECURITY ADVISORY NUMBER:
2013-097

DATE(S) ISSUED:
10/08/2013

SUBJECT:
Vulnerabilities in Microsoft Word Could Allow Remote Code Execution (MS13-086)

OVERVIEW:

Multiple vulnerabilities have been discovered in Microsoft Word that could result in remote code execution. Exploitation may occur if a user opens a specially crafted Word file using an affected version of Microsoft Office.

Successful exploitation of these vulnerabilities could result in the attacker gaining the same rights as the logged on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

SYSTEMS AFFECTED:

  • Microsoft Office 2003
  • Microsoft Office 2007
  • Microsoft Office Compatibility Pack SP3

RISK:

Government:

  • Large and medium government entities: High
  • Small government entities: High

Businesses:

  • Large and medium business entities: High
  • Small business entities: High

Home users: High

DESCRIPTION:

Two memory corruption vulnerabilities have been identified in Microsoft Word that could allow remote code execution. These vulnerabilities are caused due to the way that Microsoft Word handles objects in memory while parsing specially crafted files.

Successful exploitation of these vulnerabilities could result in the attacker gaining the same rights as the logged on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.

RECOMMENDATIONS:

We recommend the following actions be taken:

  • Apply appropriate patches provided by Microsoft to vulnerable systems immediately after appropriate testing.
  • Run all software as a non-privileged user (one without administrative privileges) to diminish the effects of a successful attack.
  • Consider viewing emails in plain text.
  • Remind users not to open e-mail attachments from unknown users or suspicious e-mails from trusted sources.
  • Remind users not to visit un-trusted websites or follow links provided by unknown or un-trusted sources.

REFERENCES:

Microsoft:

https://technet.microsoft.com/en-us/security/bulletin/ms13-086

CVE:

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-3891

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-3892