CVE-2019-1004 in Internet Explorer
Summary
by MITRE
A remote code execution vulnerability exists in the way that the scripting engine handles objects in memory in Internet Explorer, aka 'Scripting Engine Memory Corruption Vulnerability'. This CVE ID is unique from CVE-2019-1001, CVE-2019-1056, CVE-2019-1059.
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Analysis
by VulDB Data Team • 10/18/2023
This vulnerability represents a critical memory corruption flaw within Internet Explorer's scripting engine that enables remote code execution attacks. The issue stems from improper handling of objects in memory during script processing, creating a pathway for attackers to execute arbitrary code on vulnerable systems. The vulnerability specifically affects the JavaScript engine and JScript engine components that process web content, making it particularly dangerous in web browsing environments where users frequently encounter malicious content. The flaw exists in the way the engine manages memory allocation and object references, leading to potential buffer overflows or use-after-free conditions that can be exploited by remote attackers.
The technical implementation of this vulnerability involves the scripting engine's failure to properly validate memory operations when processing certain object types and script constructs. Attackers can craft malicious web pages that, when loaded in Internet Explorer, trigger the memory corruption condition through specific JavaScript code sequences. This allows for arbitrary code execution with the privileges of the logged-in user, potentially leading to full system compromise. The vulnerability is particularly concerning because it operates at the core scripting engine level, meaning that successful exploitation can bypass many traditional security controls and defenses. According to CWE standards, this maps to CWE-125: Out-of-bounds Read and CWE-787: Out-of-bounds Write, both of which represent serious memory safety issues that enable privilege escalation and arbitrary code execution.
The operational impact of this vulnerability extends beyond simple browser compromise, as it can serve as a foothold for broader network attacks. Once an attacker gains execution control through this vulnerability, they can establish persistent access, escalate privileges, or move laterally within the network. The attack surface is broad since Internet Explorer remains installed on many enterprise systems, particularly in legacy environments where modern browser adoption has not occurred. Organizations running older Windows versions such as Windows 7, Windows Server 2008, and Windows 10 versions prior to the relevant security updates are particularly at risk. The vulnerability can be exploited through various attack vectors including malicious websites, email attachments, and compromised web services that deliver malicious JavaScript payloads.
Mitigation strategies should prioritize immediate patching of affected systems with Microsoft security updates, as these address the underlying memory handling flaws in the scripting engine. Organizations should also implement browser hardening measures including disabling unnecessary scripting capabilities, implementing strict content security policies, and using sandboxing technologies to limit potential damage from successful exploitation attempts. Network-level protections such as web application firewalls and intrusion detection systems can help identify and block malicious traffic patterns associated with exploitation attempts. Security teams should also consider implementing browser isolation technologies and encouraging users to migrate to modern browser alternatives that have more robust security implementations and regular update cycles. The ATT&CK framework categorizes this vulnerability under T1203: Exploitation for Client Execution, highlighting the need for comprehensive endpoint protection and user behavior monitoring to detect and prevent exploitation attempts.