CVE-2019-5809 in Chrome
Summary
by MITRE
Use after free in file chooser in Google Chrome prior to 74.0.3729.108 allowed a remote attacker who had compromised the renderer process to perform privilege escalation via a crafted HTML page.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 06/25/2024
The vulnerability identified as CVE-2019-5809 represents a critical use-after-free flaw within Google Chrome's file chooser component that existed in versions prior to 74.0.3729.108. This vulnerability operates within the browser's renderer process and demonstrates a particularly dangerous security weakness that could be exploited by remote attackers who have already gained access to the compromised rendering environment. The flaw specifically resides in how Chrome handles file selection dialogs when processing malicious HTML content, creating a scenario where freed memory locations can be accessed and manipulated by malicious code.
The technical implementation of this vulnerability stems from improper memory management within the file chooser functionality, which allows for a use-after-free condition to occur when the renderer process handles specific HTML elements related to file input operations. When a crafted HTML page is loaded, the browser's file dialog component may release memory resources while still maintaining references to those locations, creating a window where an attacker can overwrite the freed memory with malicious data. This memory corruption can then be leveraged to execute arbitrary code with the privileges of the compromised renderer process, which typically operates with the same privileges as the user running the browser application.
The operational impact of this vulnerability extends beyond simple privilege escalation, as it provides attackers with a pathway to elevate their access level within the compromised system. The renderer process in modern browsers operates with restricted privileges compared to the system's core processes, but successful exploitation of this use-after-free condition can allow an attacker to bypass these security boundaries and potentially gain access to sensitive system resources. This type of vulnerability is particularly concerning in the context of browser-based attacks, where attackers often begin with a web-based compromise and then seek to escalate their privileges to achieve more significant system access. The vulnerability aligns with CWE-416, which specifically addresses use-after-free conditions in software applications, and represents a classic example of how memory safety issues can lead to privilege escalation in complex software environments.
The exploitation of CVE-2019-5809 typically involves crafting a malicious HTML page that triggers the vulnerable file chooser component in a specific way that causes the memory management error. Attackers can leverage this vulnerability through various delivery mechanisms including phishing emails, compromised websites, or malicious advertisements, making it particularly dangerous in real-world scenarios. The attack vector requires the attacker to already have compromised the renderer process, which can be achieved through other vulnerabilities or social engineering techniques, but once achieved, this vulnerability provides a reliable method for privilege escalation. This vulnerability also maps to several ATT&CK techniques including privilege escalation through process injection and exploitation of software vulnerabilities, demonstrating how browser-based security flaws can be leveraged within broader attack frameworks. Organizations should prioritize updating to Chrome versions 74.0.3729.108 or later, as this release includes the necessary memory management fixes that prevent the use-after-free condition from occurring. Additionally, browser hardening measures such as sandboxing, content security policies, and regular security updates remain essential defensive strategies against similar vulnerabilities in the browser ecosystem.