CVE-2018-8542 in Edge
Summary
by MITRE
A remote code execution vulnerability exists in the way that the Chakra scripting engine handles objects in memory in Microsoft Edge, aka "Chakra Scripting Engine Memory Corruption Vulnerability." This affects Microsoft Edge, ChakraCore. This CVE ID is unique from CVE-2018-8541, CVE-2018-8543, CVE-2018-8551, CVE-2018-8555, CVE-2018-8556, CVE-2018-8557, CVE-2018-8588.
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Analysis
by VulDB Data Team • 06/05/2023
The CVE-2018-8542 vulnerability represents a critical memory corruption flaw within Microsoft Edge's Chakra scripting engine, which serves as the JavaScript engine powering the browser's web content execution. This vulnerability specifically manifests when the Chakra engine processes certain objects in memory, creating conditions that allow malicious actors to manipulate memory structures beyond their intended boundaries. The flaw stems from inadequate input validation and memory management within the engine's object handling mechanisms, particularly affecting how it manages object references and memory allocation during dynamic script execution. Attackers can exploit this weakness by crafting malicious web content that, when executed in Microsoft Edge, triggers the memory corruption condition.
The technical exploitation of this vulnerability follows a classic memory corruption attack pattern where the Chakra engine fails to properly validate object states during memory operations, leading to potential arbitrary code execution. The vulnerability occurs during the processing of JavaScript objects in memory, where the engine does not adequately check bounds or validate object integrity before performing memory operations. This creates a scenario where an attacker-controlled script can manipulate memory layout and potentially overwrite critical memory regions, enabling privilege escalation or full system compromise. The vulnerability is particularly dangerous because it operates at the scripting engine level, meaning successful exploitation can bypass many traditional security boundaries that protect the operating system from web-based attacks.
From an operational perspective, this vulnerability presents a significant risk to organizations relying on Microsoft Edge for web browsing, as it allows remote code execution without requiring user interaction beyond visiting a malicious webpage. The attack surface is broad since it affects not only Microsoft Edge but also ChakraCore, which is used in various Microsoft applications and services. Security researchers have noted that exploitation typically requires sophisticated techniques to achieve reliable code execution, but the potential impact remains severe. The vulnerability's classification aligns with CWE-125, which describes out-of-bounds read conditions, and follows patterns associated with the ATT&CK technique T1059.007 for JavaScript-based execution. Organizations using affected versions of Microsoft Edge are particularly vulnerable since the flaw exists in the core engine that processes all web content, making it a prime target for nation-state actors and cybercriminals seeking persistent access to target systems.
Mitigation strategies for CVE-2018-8542 focus primarily on immediate patching of affected Microsoft Edge versions and ensuring ChakraCore implementations are updated. Microsoft released security updates addressing this vulnerability through regular monthly patches, and organizations should prioritize deployment of these updates across all affected systems. Additional protective measures include implementing browser hardening configurations, enabling sandboxing features, and deploying web application firewalls to filter malicious content. Security teams should also consider implementing network segmentation and monitoring for suspicious web traffic patterns that may indicate exploitation attempts. The vulnerability's impact extends beyond immediate exploitation to long-term security posture considerations, as it demonstrates the critical importance of maintaining up-to-date browser engines and implementing defense-in-depth strategies. Organizations should also conduct regular vulnerability assessments focusing on scripting engine security and implement automated patch management systems to reduce exposure windows.