CVE-2017-11889 in Edge
Summary
by MITRE
ChakraCore and Microsoft Edge in Windows 10 Gold, 1511, 1607, 1703, 1709, and Windows Server 2016 allows an attacker to execute arbitrary code in the context of the current user, due to how the scripting engine handles objects in memory, aka "Scripting Engine Memory Corruption Vulnerability". This CVE ID is unique from CVE-2017-11886, CVE-2017-11890, CVE-2017-11893, CVE-2017-11894, CVE-2017-11895, CVE-2017-11901, CVE-2017-11903, CVE-2017-11905, CVE-2017-11907, CVE-2017-11908, CVE-2017-11909, CVE-2017-11910, CVE-2017-11911, CVE-2017-11912, CVE-2017-11913, CVE-2017-11914, CVE-2017-11916, CVE-2017-11918, and CVE-2017-11930.
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Analysis
by VulDB Data Team • 01/26/2021
The vulnerability identified as CVE-2017-11889 represents a critical memory corruption flaw within Microsoft's ChakraCore JavaScript engine and Microsoft Edge browser implementation. This vulnerability affects multiple Windows 10 versions including Gold, 1511, 1607, 1703, and 1709, as well as Windows Server 2016, making it a widespread concern across various Microsoft operating system deployments. The flaw stems from improper handling of objects in memory by the scripting engine, creating a condition where malicious code can exploit memory management inconsistencies to achieve arbitrary code execution. This type of vulnerability falls under the CWE-125 weakness category, which specifically addresses out-of-bounds read conditions that can lead to memory corruption and potential privilege escalation.
The technical exploitation of this vulnerability occurs through a carefully crafted script that manipulates how ChakraCore manages memory objects during JavaScript execution. When the scripting engine processes malformed or specially constructed objects, it fails to properly validate memory boundaries, leading to corruption that can be leveraged by attackers. The memory corruption typically manifests as heap-based buffer overflows or use-after-free conditions, where attacker-controlled data can overwrite critical memory regions. This vulnerability aligns with ATT&CK technique T1059.007 for Windows Command Shell and T1059.001 for Command and Scripting Interpreter, as attackers can utilize the compromised scripting engine to execute malicious commands within the user context.
The operational impact of CVE-2017-11889 is significant as it allows attackers to execute arbitrary code with the privileges of the currently logged-in user, bypassing many traditional security controls. This means that successful exploitation can lead to complete system compromise without requiring administrative privileges or elevated access. The vulnerability is particularly dangerous in enterprise environments where users may have access to various applications that could trigger the malicious script execution. Attackers can leverage this vulnerability through various attack vectors including phishing emails with malicious attachments, compromised websites, or social engineering campaigns that trick users into executing malicious JavaScript code. The vulnerability's presence in multiple Windows 10 releases and Windows Server 2016 creates a broad attack surface that security teams must address across their entire infrastructure.
Mitigation strategies for CVE-2017-11889 should focus on immediate patch deployment and implementation of additional security controls. Microsoft released security updates that address this vulnerability through the Windows Update mechanism, which should be deployed immediately across all affected systems. Organizations should also implement application whitelisting policies to restrict execution of untrusted scripts and implement browser security enhancements such as enabling sandboxing features and disabling unnecessary scripting capabilities. Network-based mitigations including web application firewalls and content filtering solutions can help prevent exploitation attempts by blocking malicious payloads before they reach vulnerable systems. Security monitoring should focus on detecting anomalous script execution patterns and memory access violations that could indicate exploitation attempts. Additionally, user education programs should emphasize the importance of avoiding suspicious email attachments and websites that could contain malicious scripts designed to exploit this vulnerability, as social engineering remains a primary attack vector for this class of memory corruption flaws.