==================================================================== CERT-Renater Note d'Information No. 2016/VULN159 _____________________________________________________________________ DATE : 13/04/2016 HARDWARE PLATFORM(S): / OPERATING SYSTEM(S): Cisco IOS XR Software versions 4.2.3, 4.3.0, 4.3.4, 5.3.1. ====================================================================== KB3148532 https://technet.microsoft.com/en-us/library/security/MS16-038 _____________________________________________________________________ MS16-038 - Cumulative Security Update for Microsoft Edge (3148532) Document Metadata Bulletin Number: MS16-038 Bulletin Title: Cumulative Security Update for Microsoft Edge Severity: Critical KB Article: 3148532 Version: 1.0 Executive Summary This security update resolves vulnerabilities in Microsoft Edge. The most severe of the vulnerabilities could allow remote code execution if a user views a specially crafted webpage using Microsoft Edge. An attacker who successfully exploited the vulnerabilities could gain the same user rights as the current user. Customers whose accounts are configured to have fewer user rights on the system could be less impacted than users with administrative user rights. This security update is rated Critical for Microsoft Edge on Windows 10. Affected Software Microsoft Edge Vulnerability Information Multiple Microsoft Edge Memory Corruption Vulnerabilities Multiple remote code execution vulnerabilities exist when Microsoft Edge improperly accesses objects in memory. The vulnerabilities could corrupt memory that enables an attacker to execute arbitrary code in the context of the current user. An attacker could host a specially crafted website that is designed to exploit the vulnerabilities through Microsoft Edge, and then convince a user to view the website. The attacker could also take advantage of compromised websites and websites that accept or host user-provided content or advertisements by adding specially crafted content that could exploit the vulnerability. In all cases, however, an attacker would have no way to force users to view the attacker-controlled content. Instead, an attacker would have to convince users to take action, typically by way of enticement in an email or Instant Messenger message, or by getting them to open an attachment sent through email. An attacker who successfully exploited the 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. The update addresses the vulnerabilities by modifying how Microsoft Edge handles objects in memory. The following table contains links to the standard entry for each vulnerability in the Common Vulnerabilities and Exposures list: Vulnerability title CVE number Publicly disclosed Exploited Microsoft Browser Memory Corruption Vulnerability CVE-2016-0154 No No Microsoft Edge Memory Corruption Vulnerability CVE-2016-0155 No No Microsoft Edge Memory Corruption Vulnerability CVE-2016-0156 No No Microsoft Edge Memory Corruption Vulnerability CVE-2016-0157 No No Microsoft Edge Elevation of Privilege - CVE-2016-0158 An elevation of privilege vulnerability exists when Microsoft Edge does not properly enforce cross-domain policies, which could allow an attacker to access information from one domain and inject it into another domain. In a web-based attack scenario, an attacker could host a website in an attempt to exploit the vulnerability. In addition, compromised websites and websites that accept or host user-provided content could contain specially crafted content that could exploit the vulnerability. However, in all cases an attacker could not force a user to view the attacker-controlled content. Instead, an attacker would have to convince a user to take action. For example, an attacker could trick a user into clicking a link that takes the user to the attacker's site. An attacker who successfully exploited this vulnerability could elevate privileges in affected versions of Microsoft Edge. The vulnerability by itself does not allow arbitrary code to be run. However, the vulnerability could be used in conjunction with another vulnerability (for example, a remote code execution vulnerability) that an attacker could use to take advantage of the elevated privileges when running arbitrary code. For example, an attacker could exploit another vulnerability to run arbitrary code through Microsoft Edge, but because of the context in which processes are launched by Microsoft Edge, the code might be restricted to run at a low integrity level (very limited permissions). However, an attacker could, in turn, exploit this vulnerability to cause the arbitrary code to run at a medium integrity level (the permissions of the current user). The update addresses the vulnerability by helping to ensure that cross-domain policies are properly enforced in Microsoft Edge. The following table contains links to the standard entry for each vulnerability in the Common Vulnerabilities and Exposures list: Vulnerability title CVE number Publicly disclosed Exploited Microsoft Edge Elevation of Privilege Vulnerability CVE-2016-0158 No No Microsoft Edge Elevation of Privilege Vulnerability - CVE-2016-0161 An elevation of privilege vulnerability exists when Microsoft Edge does not properly validate JavaScript under specific conditions, potentially allowing a script to be run with elevated privileges. In a web-based attack scenario, an attacker could host a website in an attempt to exploit this vulnerability. In addition, compromised websites and websites that accept or host user-provided content could contain specially crafted content that could exploit the vulnerability. However, in all cases an attacker would have no way to force users to view the attacker-controlled content. Instead, an attacker would have to convince users to take action. For example, an attacker could trick users into clicking a link that takes them to the attacker's site. An attacker who successfully exploited the vulnerability could elevate privileges in affected versions of Microsoft Edge. An attacker could then leverage these privileges with another vulnerability to run arbitrary code with medium integrity level privileges (permissions of the current user). This vulnerability by itself does not allow arbitrary code to be run. However, this vulnerability could be used in conjunction with another vulnerability (for example, a remote code execution vulnerability) that could take advantage of the elevated privileges when running arbitrary code. For example, an attacker could exploit another vulnerability to run arbitrary code through Microsoft Edge, but because of the context in which processes are launched by Internet Explorer, the code might be restricted to run at a low integrity level (very limited permissions). However, an attacker could, in turn, exploit this vulnerability to cause the arbitrary code to run at a medium integrity level (permissions of the current user). The update addresses the vulnerability by adding additional permission validations to Microsoft Edge. The following table contains links to the standard entry for each vulnerability in the Common Vulnerabilities and Exposures list: Vulnerability title CVE number Publicly disclosed Exploited Microsoft Edge Elevation of Privilege Vulnerability CVE-2016-0161 No No ========================================================== Serveur de référence du CERT-Renater https://services.renater.fr/ssi/ ========================================================== + CERT-RENATER | tel : 01-53-94-20-44 + + 23 - 25 Rue Daviel | fax : 01-53-94-20-41 + + 75013 Paris | email: cert@support.renater.fr + ==========================================================