NY.gov Portal State Agency Listing
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:
2013-121

DATE(S) ISSUED:
12/10/2013

SUBJECT:
Vulnerabilities in Microsoft Exchange Server Could Allow Remote Code Execution (MS13-105)

OVERVIEW:

Multiple vulnerabilities have been discovered in Microsoft Exchange Server that could allow remote code execution. Microsoft Exchange provides email, calendar, and contacts for corporate environments.  Exploitation of these vulnerabilities could occur by an attacker sending an email message containing a specially content to an affected Exchange server. Successful exploitation could result in the attacker gaining the same user rights as the LocalService account or the logged on user. Depending on the privileges associated with the account, an attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

SYSTEMS AFFECTED:

  • Microsoft Exchange Server 2007
  • Microsoft Exchange Server 2010
  • Microsoft Exchange Server 2013

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: N/A

DESCRIPTION:
Multiple vulnerabilities have been discovered in Microsoft Exchange Server that could allow remote code execution. Two of the vulnerabilities exist in the WebReady Document Viewing feature. Two other vulnerabilities are caused by the Exchange Server not properly validating input. Exploitation of these vulnerabilities could be caused by an attacker sending specially crafted content to the Exchange Server or as an email attachment.  Successful exploitation could result in the attacker gaining the same user rights as the LocalService account or the logged on user. Depending on the privileges associated with the account, an attacker could then 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.
  • Evaluate the relative need for WebReady Document viewing and disable if deemed non-essential.
  • 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:

https://technet.microsoft.com/en-us/security/bulletin/ms13-105

CVE:
http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-5763
http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-5791
http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-1330
http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-5072

Deborah A. Snyder

Acting Chief Information Security Officer


 

Cyber Security

GIS