CVE-2017-8640 in Edge
Summary
by MITRE
Microsoft Edge in Windows 10 Gold, 1511, 1607, 1703, and Windows Server 2016 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-2017-8638, CVE-2017-8639, 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 • 12/14/2025
This vulnerability represents a critical memory corruption flaw within Microsoft Edge's JavaScript engines that affects multiple Windows 10 versions and Windows Server 2016. The vulnerability stems from improper handling of objects in memory during content rendering processes, creating a pathway for remote code execution attacks. The flaw specifically impacts the scripting engine's memory management capabilities, allowing attackers to manipulate memory structures and potentially execute malicious code with the privileges of the current user. This type of vulnerability is particularly dangerous because it operates at the browser engine level, where attackers can leverage the JavaScript engine's memory handling to bypass security mechanisms and gain unauthorized system access.
The technical nature of this vulnerability aligns with CWE-125, which describes out-of-bounds read conditions in memory management systems, and CWE-787, which covers out-of-bounds writes in buffer operations. These classifications indicate that the vulnerability occurs when the JavaScript engine attempts to access or modify memory locations beyond their allocated boundaries. The exploitation typically involves crafting malicious web content that triggers specific memory corruption patterns within Edge's rendering engine, particularly in how it handles object references and memory allocation during JavaScript execution. Attackers can leverage this flaw through drive-by downloads, malicious websites, or compromised web applications that render content in the vulnerable browser environment.
From an operational perspective, this vulnerability creates significant risk for enterprise environments where Microsoft Edge is the default browser or where users frequently access untrusted web content. The attack surface is broad since it affects multiple Windows 10 releases including the widely deployed 1511, 1607, and 1703 versions, as well as Windows Server 2016 deployments. The remote code execution capability means that successful exploitation could result in complete system compromise, data exfiltration, or establishment of persistent backdoors. The vulnerability's presence in the scripting engine makes it particularly challenging to detect and prevent through traditional network security measures, as the attack occurs within the browser's trusted execution environment.
Organizations should prioritize immediate patch deployment through Microsoft's regular security updates, as this vulnerability was addressed in the August 2017 security bulletin. Network segmentation and browser hardening measures can provide additional defense layers, including implementing strict content security policies and disabling unnecessary JavaScript features. The vulnerability also maps to several ATT&CK techniques including T1059.007 for script-based execution and T1203 for exploitation of software vulnerabilities. Security teams should monitor for indicators of compromise related to unusual JavaScript execution patterns or memory access anomalies that might suggest exploitation attempts. Given the nature of the vulnerability, regular security awareness training for users about avoiding suspicious web content and maintaining updated software versions remains crucial for overall security posture.