CVE-2017-0064 in Internet Explorer
Summary
by MITRE
A security feature bypass vulnerability exists in Internet Explorer that allows for bypassing Mixed Content warnings, aka "Internet Explorer Security Feature Bypass Vulnerability."
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Analysis
by VulDB Data Team • 12/22/2020
The CVE-2017-0064 vulnerability represents a critical security flaw in Microsoft Internet Explorer that undermines the browser's mixed content protection mechanisms. This vulnerability resides within the browser's security architecture and specifically targets the way Internet Explorer handles mixed content warnings that are designed to protect users from potentially malicious interactions between secure and insecure web resources. The flaw allows attackers to circumvent these essential security warnings, effectively disabling the browser's ability to alert users when they are accessing content that mixes secure and insecure elements. This bypass occurs at the protocol handling level where Internet Explorer fails to properly validate the security context of resources being loaded, creating an avenue for attackers to deliver malicious content while appearing to maintain a secure connection.
The technical implementation of this vulnerability stems from insufficient validation within Internet Explorer's security model when processing web content that contains both secure and insecure resources. When a user navigates to a secure website that attempts to load resources from insecure sources, the browser should display a mixed content warning to alert the user of potential security risks. However, CVE-2017-0064 allows attackers to craft web pages or manipulate existing content in such a way that these warnings are suppressed or bypassed entirely. The vulnerability specifically affects how Internet Explorer processes certain HTTP and HTTPS interactions, particularly when dealing with embedded resources like images, scripts, or iframes that originate from different security contexts. This flaw can be exploited through various attack vectors including malicious websites, compromised web servers, or through social engineering techniques that trick users into visiting vulnerable pages.
The operational impact of this vulnerability extends beyond simple security warnings being bypassed, as it creates a pathway for more sophisticated attacks that could compromise user data and system integrity. Attackers can leverage this vulnerability to deliver malicious content while maintaining the appearance of a secure connection, making it significantly harder for users to detect potential threats. The bypass affects users across various operating systems including Windows 7, Windows 8.1, Windows 10, and Windows Server 2012, making it a widespread concern for enterprise environments. This vulnerability aligns with CWE-693, which addresses protection mechanism failures, and represents a clear violation of the principle of least privilege in security design. Organizations using Internet Explorer for business operations face heightened risk of man-in-the-middle attacks, credential theft, and data exfiltration, as users may unknowingly interact with compromised resources that appear to be secure. The vulnerability also impacts the browser's security model by undermining user trust in the warning systems that are meant to protect against such threats.
Mitigation strategies for CVE-2017-0064 require immediate remediation through Microsoft security updates and comprehensive security policy enforcement. Organizations should prioritize installing the relevant security patches released by Microsoft as part of their regular update procedures, as these patches address the core validation issues within Internet Explorer's mixed content handling. System administrators should implement network-level controls to monitor and block insecure content delivery, particularly in enterprise environments where Internet Explorer usage remains prevalent. Browser hardening techniques including disabling unnecessary features, implementing strict content security policies, and configuring security zones appropriately can provide additional defense layers. The vulnerability demonstrates the importance of maintaining up-to-date security controls and highlights the need for organizations to transition away from legacy browsers that may contain unpatched security flaws. From an att&ck framework perspective, this vulnerability maps to techniques involving privilege escalation and credential access, as attackers can exploit the bypass to gain unauthorized access to user sessions and sensitive information. Regular security awareness training for users about the importance of mixed content warnings and the risks associated with visiting untrusted websites remains crucial in mitigating the operational impact of this vulnerability.