Cumulative Security Update for Internet Explorer

ITS Advisory Number: 
2016-147
Date(s) Issued: 
Tuesday, September 13, 2016
Subject: 
Cumulative Security Update for Internet Explorer
Overview: 

Multiple vulnerabilities have been discovered in Microsoft Internet Explorer the most severe of which could allow remote code execution if a user views a specially crafted web page. An attacker who successfully exploited these vulnerabilities could gain the same user rights as the current user. If the current user is logged on with administrative user rights, an attacker could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

Systems Affected: 
  • Internet Explorer 9

  • Internet Explorer 10

  • Internet Explorer 11

RISK
GOVERNMENT
Large and medium government entities: 
High
Small government entities: 
Medium
BUSINESS
Large and medium business entities: 
High
Small business entities: 
Medium
Home Users: 
Low
Description: 

Microsoft Internet Explorer is prone to multiple vulnerabilities that could allow remote code execution. The vulnerabilities are as follows:

 

  • Four memory corruption vulnerabilities exist when Internet Explorer improperly accesses objects in memory (CVE-2016-3247, CVE-2016-3295, CVE-2016-3297, CVE-2016-3324)

  • Two information disclosure vulnerabilities exist when Internet Explorer improperly handles objects in memory (CVE-2016-3325, CVE-2016-3351)

  • One remote code execution vulnerability exists in the way that the Microsoft OLE Automation mechanism and the VBScript Scripting Engine in Internet Explorer access objects in memory (CVE-2016-3375)

  • One information disclosure vulnerability exists when Internet Explorer improperly handles cross-origin requests (CVE-2016-3291)

  • One security feature bypass vulnerability exists when Internet Explorer handles files from the Internet zone (CVE-2016-3353)

  • One privilege escalation vulnerability exists when Internet Explorer fails a check allowing a sandbox escape (CVE-2016-3292)

 

The most severe of these vulnerabilities could allow an attacker to execute remote code by luring a victim to visit a specially crafted malicious website. If the current user is logged on with administrative user rights, an attacker could take control of an affected system. 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. 

Actions: 
  • After appropriate testing, install updates provided by Microsoft to the vulnerable systems.
  • Remind users not to visit websites or follow links provided by unknown or untrusted sources.
  • Inform and educate users regarding the threats posed by hypertext links contained in emails or attachments especially from untrusted sources
  • Apply the principle of Least Privilege to all systems and services.