The following cyber advisory was issued by the New York State Office of Information Technology Services and is intended for State government entities. The information may or may not be applicable to the general public and, accordingly, the State does not warrant its use for any specific purposes.

ITS ADVISORY NUMBER:
2013-098

DATE(S) ISSUED:
10/8/2013

SUBJECT:
Vulnerabilities in Microsoft SharePoint Server Could Allow Remote Code Execution (2885089)

OVERVIEW:

Vulnerabilities found within Microsoft SharePoint Server could allow remote code execution. Microsoft SharePoint is a software platform and a family of software products designed for collaboration, file sharing and web publishing. Successful exploitation of these vulnerabilities may result in either an attacker gaining the same privileges as the logged on user, or gaining session authentication credentials. Depending on the privileges associated with the user, the attacker could install programs; view, change or delete data or create new accounts with full user rights.

SYSTEMS AFFECTED:

  • Microsoft SharePoint Server 2007
  • Microsoft SharePoint Server 2010
  • Microsoft SharePoint Server 2013
  • Microsoft Office Web Apps 2010

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: Low

DESCRIPTION:
Vulnerabilities found within Microsoft SharePoint Server could allow remote code execution. The details are as follows;

  • Microsoft Excel Memory Corruption Vulnerability - CVE-2013-3889

A remote code execution vulnerability exists in the way that affected Microsoft Office Services and Web Apps parse content in specially crafted files. This vulnerability requires that a user open a specially crafted Office file with an affected version of Microsoft Excel software.

  • Parameter Injection Vulnerability - CVE-2013-3895

An elevation of privilege vulnerability exists in Microsoft SharePoint Server. The vulnerability is caused when SharePoint Server does not properly protect against a practice known as clickjacking in a SharePoint page. Clickjacking is an online threat whereby an attacker's webpage deceives a user into clicking specially crafted content by disguising it as legitimate content.

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

RECOMMENDATIONS:
We recommend the following actions be taken:

  • Apply appropriate patches provided by Microsoft to vulnerable systems immediately after appropriate testing.
  • Remind users not to visit un-trusted websites or follow links provided by unknown or un-trusted sources.
  • Run all software as a non-privileged user (one without administrative privileges) to diminish the effects of a successful attack.
  • Remind users not to visit un-trusted websites or follow links provided by unknown or un-trusted sources.

REFERENCES:
Microsoft:

http://technet.microsoft.com/en-us/security/bulletin/ms13-084

CVE:
http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-3889
http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-3895

Deborah A. Snyder

Acting Chief Information Security Officer


 

Cyber Security

GIS