CVE-2019-5843 in Chrome
Summary
by MITRE
Out of bounds memory access in JavaScript in Google Chrome prior to 74.0.3729.108 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page.
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Analysis
by VulDB Data Team • 03/10/2024
The vulnerability identified as CVE-2019-5843 represents a critical out-of-bounds memory access flaw within Google Chrome's JavaScript engine, specifically affecting versions prior to 74.0.3729.108. This issue resides in the browser's handling of JavaScript objects and memory management, creating a potential pathway for remote code execution through maliciously crafted web content. The flaw manifests when Chrome processes certain JavaScript constructs that lead to improper memory boundaries during object manipulation, allowing attackers to corrupt heap memory structures. The vulnerability is particularly concerning as it operates entirely within the browser's JavaScript execution environment, making it accessible through standard web browsing activities without requiring any additional privileges or user interaction beyond visiting a malicious webpage.
The technical implementation of this vulnerability stems from inadequate bounds checking within Chrome's V8 JavaScript engine, which is responsible for executing JavaScript code in the browser. When processing specific patterns of JavaScript code that involve array operations or object property manipulations, the engine fails to properly validate memory access boundaries. This allows an attacker to craft HTML pages containing malicious JavaScript that, when executed by the browser, triggers memory corruption by writing data beyond allocated memory regions. The flaw typically involves scenarios where JavaScript code attempts to access array elements or object properties that exceed their allocated memory space, leading to heap corruption that can be exploited to execute arbitrary code. This type of vulnerability falls under CWE-129, which specifically addresses insufficient bounds checking, and represents a classic example of heap-based buffer overflow conditions.
The operational impact of CVE-2019-5843 extends beyond simple memory corruption, as it provides attackers with a potential pathway for remote code execution in the context of the victim's browser. Attackers can leverage this vulnerability by hosting malicious web pages that contain crafted JavaScript code designed to trigger the out-of-bounds memory access condition. Once exploited, the heap corruption can be used to overwrite critical memory structures, potentially allowing attackers to execute arbitrary code with the privileges of the browser process. This makes the vulnerability particularly dangerous in environments where users browse untrusted websites or receive phishing emails containing malicious links. The attack surface is broad since any user visiting a compromised website could be affected, making this a significant concern for enterprise environments and individual users alike.
Mitigation strategies for CVE-2019-5843 primarily focus on immediate browser updates to versions 74.0.3729.108 and later, which contain patches addressing the heap corruption vulnerability. Organizations should implement comprehensive patch management procedures to ensure all Chrome installations are updated promptly, particularly in enterprise environments where multiple browsers may be in use. Additional protective measures include implementing web application firewalls, deploying content security policies to restrict script execution, and configuring browser security settings to limit potential exploitation vectors. The vulnerability aligns with ATT&CK technique T1203, which covers legitimate program execution through browser-based attacks, and organizations should consider implementing monitoring for suspicious JavaScript behavior patterns that could indicate exploitation attempts. Network-level protections such as intrusion detection systems can also help identify attempts to exploit this vulnerability by monitoring for known malicious payload patterns associated with this class of heap corruption attacks.