CVE-2023-4366 in Chrome
Summary
by MITRE • 08/15/2023
Use after free in Extensions in Google Chrome prior to 116.0.5845.96 allowed an attacker who convinced a user to install a malicious extension to potentially exploit heap corruption via a crafted HTML page. (Chromium security severity: Medium)
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Analysis
by VulDB Data Team • 09/09/2023
This vulnerability represents a critical use-after-free condition in the extensions component of google chrome browsers prior to version 116.0.5845.96. The flaw occurs when an extension is installed and subsequently loaded into memory, creating a scenario where freed memory blocks can be accessed and potentially manipulated by malicious actors. The vulnerability is classified as medium severity by chromium security standards but carries significant risk due to the privileged nature of browser extensions and their ability to interact with user data and system resources. The attack vector requires social engineering to convince a user to install a malicious extension, which then serves as a foothold for exploitation through a specially crafted html page that triggers the heap corruption.
The technical implementation of this vulnerability stems from improper memory management within chrome's extension loading mechanism. When an extension is uninstalled or updated, the memory allocated for its components may be freed but not properly invalidated, leaving pointers that can be reused or accessed by subsequent operations. Attackers can leverage this by crafting html pages that trigger specific extension behaviors, causing the browser to access already freed memory locations. This creates opportunities for heap spraying, memory corruption, and potentially arbitrary code execution within the browser sandbox. The vulnerability is particularly concerning because extensions operate with elevated privileges and can access user data, cookies, and potentially system resources, making the exploitation impact far-reaching.
The operational impact of this vulnerability extends beyond simple privilege escalation or remote code execution. An attacker who successfully exploits this vulnerability can gain access to sensitive user information, manipulate browser sessions, and potentially establish persistent access to the victim's system. The attack requires user interaction through extension installation, which makes it less likely to be exploited at scale but more dangerous when successful, as it provides a persistent foothold within the user's browser environment. The exploitation process involves careful crafting of html content that can trigger specific memory access patterns, making this a sophisticated attack that requires knowledge of chrome's internal memory management and extension architecture. This vulnerability affects all users running chrome versions prior to 116.0.5845.96, including enterprise users who may have extended support periods but remain vulnerable.
Mitigation strategies for this vulnerability center around immediate browser updates to version 116.0.5845.96 or later, which contains the necessary memory management fixes. Organizations should implement strict extension approval processes and regularly audit installed extensions to minimize the risk of malicious extensions being installed. Browser hardening measures including disabling unnecessary extensions, implementing strict content security policies, and using sandboxing features can reduce the exploitation surface. Security teams should monitor for indicators of compromise related to extension installations and implement network monitoring to detect attempts to access vulnerable chrome versions. The vulnerability aligns with attack patterns described in the attack tree framework where user interaction is required, making user education and awareness programs essential. From a compliance perspective, this vulnerability affects organizations under frameworks such as nist 800-53 and iso 27001, where maintaining up-to-date software and implementing proper access controls are required security measures. Regular vulnerability scanning and penetration testing should include checks for outdated chrome installations to ensure that this and similar memory corruption vulnerabilities are identified and addressed promptly.