==================================================================== CERT-Renater Note d'Information No. 2016/VULN321 _____________________________________________________________________ DATE : 14/09/2016 HARDWARE PLATFORM(S): / OPERATING SYSTEM(S): Systems running Internet Explorer. ===================================================================== KB3183038 https://technet.microsoft.com/en-us/library/security/MS16-104 ____________________________________________________________________ MS16-104: Cumulative Security Update for Internet Explorer (3183038) - Critical Executive Summary This security update resolves vulnerabilities in Internet Explorer. The most severe of the vulnerabilities could allow remote code execution if a user views a specially crafted webpage using Internet Explorer. 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. This security update is rated Critical for Internet Explorer 9 (IE 9), and Internet Explorer 11 (IE 11) on affected Windows clients, and Moderate for Internet Explorer 9 (IE 9), Internet Explorer 10 (IE 10), and Internet Explorer 11 (IE 11) on affected Windows servers. Affected Software Internet Explorer 9 Internet Explorer 10 Internet Explorer 11 Multiple Microsoft Internet Explorer Memory Corruption Vulnerabilities Multiple remote code execution vulnerabilities exist in the way that Internet Explorer accesses objects in memory. The vulnerabilities could corrupt memory in a way that could allow an attacker to execute arbitrary code in the context of the current user. 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, the 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. An attacker could host a specially crafted website that is designed to exploit the vulnerabilities through Internet Explorer, and then convince a user to view the website. The attacker could also take advantage of compromised websites, or websites that accept or host user-provided content or advertisements, by adding specially crafted content that could exploit the vulnerabilities. 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 via an enticement in email or instant message, or by getting them to open an email attachment. The update addresses the vulnerabilities by modifying how Internet Explorer handles objects in memory. The following table contains links to the standard entry for each vulnerability in the Common Vulnerabilities and Exposures list: Vulnerability Information Vulnerability title CVE number Publicly disclosed Exploited Microsoft Browser Memory Corruption Vulnerability CVE-2016-3247 No No Microsoft Browser Memory Corruption Vulnerability CVE-2016-3295 No No Microsoft Browser Memory Corruption Vulnerability CVE-2016-3297 No No Internet Explorer Memory Corruption Vulnerability CVE-2016-3324 No No Scripting Engine Memory Corruption Vulnerability CVE-2016-3375 A 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. The vulnerability could corrupt memory in a way that could allow an attacker to execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, the 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. An attacker could host a specially crafted website that is designed to exploit the vulnerability through Internet Explorer, and then convince a user to view the website. The attacker could also take advantage of compromised websites, or 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 via an enticement in email or instant message, or by getting them to open an email attachment. Note that you must install two updates to be protected from the Scripting Engine Memory Corruption Vulnerability CVE-2016-3375: The update in this bulletin, MS16-104, and the update in MS16-116. The updates address the vulnerability by modifying how the Microsoft OLE Automation mechanism and the VBScript Scripting Engine in Internet Explorer handle 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 Scripting Engine Memory Corruption Vulnerability CVE-2016-3375 No No Internet Explorer Elevation of Privilege Vulnerability CVE-2016-3292 An elevation of privilege vulnerability exists when Internet Explorer fails a check, allowing sandbox escape. An attacker who successfully exploited the vulnerability could use the sandbox escape to elevate privileges on an affected system. This vulnerability by itself does not allow arbitrary code execution; however, it could allow arbitrary code to be run if the attacker uses it in combination with one or more vulnerabilities (such as a remote code execution vulnerability or another elevation of privilege vulnerability) that is capable of leveraging the elevated privileges when code execution is attempted. The update addresses the vulnerability by correcting how Internet Explorer handles zone and integrity settings. 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 Elevation of Privilege Vulnerability CVE-2016-3292 No No Multiple Internet Explorer Information Disclosure Vulnerabilities Multiple information disclosure vulnerabilities exist in the way that Internet Explorer handles objects in memory. An attacker who successfully exploited the vulnerabilities could obtain information to further compromise a target system. In a web-based attack scenario an attacker could host a website that is used to attempt to exploit the vulnerabilities. Additionally, compromised websites and websites that accept or host user-provided content could contain specially crafted content that could be used to exploit the vulnerabilities. However, in all cases an attacker would have no way to force users to view 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. The update addresses the vulnerabilities by correcting how certain functions handle 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 Information Disclosure Vulnerability CVE-2016-3325 No No Microsoft Browser Information Disclosure Vulnerability CVE-2016-3351 No Yes Microsoft Browser Information Disclosure Vulnerability CVE-2016-3291 An information disclosure vulnerability exists in the way that affected Microsoft browsers handle cross-origin requests. An attacker who successfully exploited this vulnerability could determine the origin of all of the web pages in the affected browser. In a web-based attack scenario, an attacker could host a website that is used to attempt to exploit the vulnerability. Additionally, compromised websites and websites that accept or host user-provided content could contain specially crafted content that could be used to exploit the vulnerabilities. However, in all cases an attacker would have no way to force users to view 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. The security update addresses the vulnerabilities by correcting how affected browsers handle cross-origin resources. 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 Information Disclosure Vulnerability CVE-2016-3291 No No Internet Explorer Security Feature Bypass - CVE-2016-3353 A security feature bypass opportunity exists in the way that Internet Explorer handles files from the Internet zone. In a web-based attack scenario an attacker could host a malicious website that is designed to exploit the security feature bypass. Alternatively, in an email or instant message attack scenario, the attacker could send the targeted user a specially crafted .URL file that is designed to exploit the bypass. Additionally, compromised websites or websites that accept or host user-provided content could contain specially crafted content that could be used to exploit the security feature bypass. In all cases, however, an attacker would have no way to force users to view attacker-controlled content. Instead, an attacker would have to convince users to take action. For example, an attacker could entice users into clicking a link that directs them to the attacker's site or send a malicious attachment. The update addresses the security feature by correcting how Internet Explorer handles .URL files 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 Internet Explorer Security Feature Bypass CVE-2016-3353 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 + ==========================================================