MS-ISAC CYBERSECURITY ADVISORIES

MS-ISAC ADVISORY NUMBER:
2016-182

DATE(S) ISSUED:
12/13/2016

SUBJECT:
Cumulative Security Update for Microsoft Edge (MS16-145)

OVERVIEW:

Multiple vulnerabilities have been discovered in Microsoft Edge, the most severe of which could allow remote code execution if a user views a specially crafted web page. Microsoft Edge replaced Internet Explorer as the default browser on Windows 10. Successful exploitation of these vulnerabilities could result in an attacker gaining the same privileges 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 those who operate with administrative user rights.

THREAT INTELLIGENCE:

Two information disclosure (CVE-2016-7206, CVE-2016-7282) vulnerabilities and a security feature bypass (CVE-2016-7281) vulnerability have been publicly disclosed. There are no reports of these vulnerabilities being exploited in the wild.

SYSTEMS AFFECTED:

· Windows 10, 10 Version 1511, 10 Version 1607

· Windows Server 2016

RISK:

Government:

· Large and medium government entities: High

· Small government entities: Medium

Businesses:

· Large and medium business entities: High

· Small business entities: Medium

Home users: Low

TECHNICAL SUMMARY:

Multiple vulnerabilities have been discovered in Microsoft Edge, the most severe of which could allow for remote code execution if a user views a specially crafted web page. Details of these vulnerabilities are as follows:

· Two remote code execution vulnerabilities exist when affected Microsoft browsers improperly access objects in memory. (CVE-2016-7181, CVE-2016-7279)

· Three information disclosure vulnerabilities exist when Microsoft Browsers do not properly validate content under specific conditions. (CVE-2016-7206, CVE-2016-7280, CVE-2016-7282)

· Five remote code execution vulnerabilities exist in the way affected Microsoft scripting engines render when handling objects in memory in Microsoft browsers. (CVE-2016-7287, CVE-2016-7286, CVE-2016-7288, CVE-2016-7296, CVE-2016-7297)

· A security feature bypass vulnerability exists when the Microsoft browsers fail to correctly apply Same Origin Policy for scripts running inside Web Workers. (CVE-2016-7281)

Successful exploitation of these vulnerabilities could result in an attacker gaining the same privileges 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 those 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.

· Remind users not to visit un-trusted websites or follow links provided by unknown or un-trusted sources.

· Inform and educate users regarding the threats posed by hypertext links contained in emails or attachments, especially those from un-trusted sources.

· Apply the Principle of Least Privilege to all systems and services.

REFERENCES:

Microsoft:

https://technet.microsoft.com/en-us/library/security/ms16-145.aspx

CVE:

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-7181

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-7206

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-7279

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-7280

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-7281

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-7282

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-7286

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-7287

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-7288

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-7296

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-7297