MS-ISAC CYBERSECURITY ADVISORIES

MS-ISAC ADVISORY NUMBER:
2016-153

DATE(S) ISSUED:
10/11/2016

SUBJECT:
Cumulative Security Update for Microsoft Edge (MS16-119)

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.

THREAT INTELLIGENCE:

There are reports of a scripting engine remote code execution vulnerability (CVE-2016-7189) being exploited in the wild.

SYSTEMS AFFECTED:

· Windows 10

· Windows 10 (Version 1511)

· Windows 10 (Version 1607)

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 that could allow for remote code execution. Details of these vulnerabilities are as follows:

· One memory corruption vulnerability exists when Microsoft Edge improperly handles objects in memory (CVE-2016-3331)

· Six scripting engine memory corruption vulnerabilities exist in the way the Chakra JavaScript engine renders when handling objects in memory (CVE-2016-3382, CVE-2016-3386, CVE-2016-3389, CVE-2016-3390, CVE-2016-7190, CVE-2016-7194)

· One information disclosure vulnerability exists when Microsoft Edge improperly handles objects in memory (CVE-2016-3267)

· One information disclosure vulnerability exists when Microsoft Edge leaves credential data in memory (CVE-2016-3391)

· One scripting engine remote code execution vulnerability exists when Microsoft Edge improperly handles objects in memory (CVE-2016-7189)

· Two elevation of privilege vulnerabilities exist when Microsoft Edge fails to properly secure private namespace (CVE-2016-3388, CVE-2016-3387)

· One security bypass vulnerability exists when the Edge Content Security Policy Fails to properly handle validation of certain specially crafted documents (CVE-2016-3392)

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. Customers 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/ms16-119.aspx

CVE:

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-3267

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-3331

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-3382

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-3386

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-3387

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-3388

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-3389

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-3390

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-3391

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-3392

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-7189

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-7190

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-7194