Cumulative Security Update for Internet Explorer (MS15-043)

ITS Advisory Number: 
2015-052
Date(s) Issued: 
Tuesday, May 12, 2015
Subject: 
Cumulative Security Update for Internet Explorer (MS15-043)
Overview: 

Multiple vulnerabilities have been discovered in Microsoft's web browser, Internet Explorer. These vulnerabilities could allow remote code execution or an elevation of privilege if a user views a specially crafted webpage in Internet Explorer. An attacker who successfully exploits this vulnerability could gain the same user rights as the current user. Depending on the privileges associated with the user, an attacker could install programs; view, change, or delete data; or create new accounts with full user rights.

Systems Affected: 
  • Internet Explorer 11
  • Internet Explorer 10
  • Internet Explorer 9
  • Internet Explorer 8
  • Internet Explorer 7
  • Internet Explorer 6
RISK
GOVERNMENT
Large and medium government entities: 
High
Small government entities: 
High
BUSINESS
Large and medium business entities: 
High
Small business entities: 
High
Home Users: 
High
Description: 

The following vulnerabilities were discovered in Internet Explorer:

Security Feature bypasses exist:

  • When the VBScript engine fails to use the Address Space Layout Randomization (ASLR) security feature, allowing an attacker to more reliably predict the memory offsets of specific instructions in a given call stack. [CVE-2015-1684]
  • When the JScript and VBScript engines fail to use the Address Space Layout Randomization (ASLR) security feature, allowing an attacker to more reliably predict the memory offsets of specific instructions in a given call stack. [CVE-2015-1686]
  • When Internet Explorer fails to use the Address Space Layout Randomization (ASLR) security feature, allowing an attacker to more reliably predict the memory offsets of specific instructions in a given call stack. [CVE-2015-1685]

Multiple elevation of privilege vulnerabilities exist:

  • When Internet Explorer does not properly validate permissions under specific conditions, potentially allowing script to be run with elevated privileges.

An information disclosure vulnerability exists: [CVE-2015-1688, CVE-2015-1703, CVE-2015-1704, CVE-2015-1713]

  • When Internet Explorer does not properly restrict access to the clipboard of a user who visits a website. The vulnerability could allow data stored in the Windows clipboard to be accessed by a malicious site. [CVE-2015-1692]

Multiple memory corruption vulnerabilities exist:

  • When Internet Explorer improperly accesses objects in memory. These vulnerabilities could corrupt memory in such a way that an attacker could execute arbitrary code in the context of the current user. [CVE-2015-1658, CVE-2015-1689, CVE-2015-1691, CVE-2015-1694, CVE-2015-1705, CVE-2015-1706, CVE-2015-1708, CVE-2015-1709, CVE-2015-1710, CVE-2015-1711, CVE-2015-1712, CVE-2015-1714, CVE-2015-1717, CVE-2015-1718]

These vulnerabilities could allow remote code execution or an elevation of privilege if a user views a specially crafted webpage in Internet Explorer. An attacker who successfully exploits this vulnerability could gain the same user rights as the current user. Depending on the privileges associated with the user, an attacker could install programs; view, change, or delete data; or create new accounts with full user rights.

Actions: 

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.
  • Remind users not to visit un-trusted websites or follow links provided by unknown or un-trusted sources.
  • Do not open email attachments from unknown or untrusted sources or suspicious emails from trusted sources.