CVE-2017-8638 in Edge
Summary
by MITRE
Microsoft Edge in Microsoft Windows 10 1703 allows an attacker to execute arbitrary code in the context of the current user due to the way that Microsoft browser JavaScript engines render content when handling objects in memory, aka "Scripting Engine Memory Corruption Vulnerability". This CVE ID is unique from CVE-2017-8634, CVE-2017-8635, CVE-2017-8636, CVE-2017-8639, CVE-2017-8640, CVE-2017-8641, CVE-2017-8645, CVE-2017-8646, CVE-2017-8647, CVE-2017-8655, CVE-2017-8656, CVE-2017-8657, CVE-2017-8670, CVE-2017-8671, CVE-2017-8672, and CVE-2017-8674.
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Analysis
by VulDB Data Team • 01/07/2021
This vulnerability represents a critical memory corruption flaw within Microsoft Edge's JavaScript engine that affects Windows 10 version 1703. The issue stems from improper handling of objects in memory during content rendering processes, creating a pathway for remote code execution attacks. Attackers can exploit this weakness by crafting malicious web content that triggers the vulnerable JavaScript engine behavior, ultimately allowing arbitrary code execution with the privileges of the currently logged-in user. The vulnerability specifically targets the scripting engine's memory management mechanisms, making it particularly dangerous as it operates at the core level of browser functionality where user interactions are processed.
The technical nature of this flaw aligns with CWE-125, which describes out-of-bounds read vulnerabilities, and is classified under the broader category of memory corruption issues that enable privilege escalation attacks. From an operational perspective, this vulnerability demonstrates the inherent risks present in complex browser environments where JavaScript engines must efficiently manage memory while processing untrusted content. The attack surface is significant as it leverages the browser's rendering pipeline, making it accessible through standard web browsing activities without requiring any special privileges or complex exploitation techniques. The vulnerability's impact extends beyond simple code execution to potentially enable full system compromise when combined with other attack vectors or when users are tricked into visiting malicious websites.
The exploitation of this vulnerability follows established patterns found in the ATT&CK framework under the T1059.007 technique for command and script interpreter, specifically targeting the Windows Script Host and JavaScript engines. Organizations using Windows 10 version 1703 are particularly at risk as the vulnerability exists in the default browser configuration without requiring any additional malicious software installation. The memory corruption aspect makes this vulnerability particularly challenging to detect and prevent through traditional signature-based methods, as it can manifest in various forms depending on how the JavaScript engine processes different types of content. Security researchers have noted that the vulnerability's exploitation often requires precise timing and specific memory layout conditions, making it suitable for advanced persistent threat actors who can develop sophisticated attack chains.
Mitigation strategies should focus on immediate patch deployment through Microsoft's regular security updates, as well as network-based protections such as web application firewalls that can detect and block malicious JavaScript patterns. Organizations should also implement browser hardening measures including disabling unnecessary JavaScript features, implementing strict content security policies, and maintaining comprehensive monitoring of browser-related system calls. The vulnerability highlights the importance of keeping browser environments updated and demonstrates how seemingly minor memory management issues can create significant security risks in complex software ecosystems. Security teams should also consider implementing user behavior analytics to detect anomalous JavaScript execution patterns that might indicate exploitation attempts, while maintaining awareness of the broader attack landscape that includes similar vulnerabilities in other browser components.