CVE-2011-3076 in iOS
Summary
by MITRE
Use-after-free vulnerability in Google Chrome before 18.0.1025.151 allows remote attackers to cause a denial of service or possibly have unspecified other impact via vectors related to focus handling.
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Analysis
by VulDB Data Team • 01/11/2025
The vulnerability identified as CVE-2011-3076 represents a critical use-after-free flaw in Google Chrome browser versions prior to 18.0.1025.151, which creates significant security risks for users and organizations relying on web browser functionality. This type of vulnerability occurs when a program continues to reference memory that has already been freed, potentially leading to unpredictable behavior and exploitation opportunities. The specific weakness manifests within the browser's focus handling mechanisms, which are fundamental components responsible for managing user interactions and element activation within web pages.
The technical implementation of this vulnerability stems from improper memory management during focus change operations within Chrome's rendering engine. When web pages contain specific combinations of HTML elements and JavaScript code that trigger focus events, the browser's memory allocation and deallocation processes fail to properly track the lifecycle of allocated memory blocks. This mismanagement creates a scenario where freed memory locations may still be referenced by subsequent operations, particularly when handling focus-related events such as tab navigation, element activation, or user interaction sequences. The flaw operates at the intersection of browser rendering logic and memory management, making it particularly challenging to detect and mitigate.
The operational impact of this vulnerability extends beyond simple denial of service conditions to potentially enable more severe security consequences including arbitrary code execution and system compromise. Remote attackers can exploit this weakness by crafting malicious web pages that, when loaded in affected Chrome versions, trigger the use-after-free condition during focus handling operations. The unspecified other impacts referenced in the vulnerability description suggest that exploitation could potentially lead to privilege escalation, data corruption, or complete browser sandbox escape. Attackers can leverage this vulnerability through various delivery mechanisms including malicious websites, phishing campaigns, or compromised web applications that serve content designed to trigger the specific memory management flaw.
This vulnerability aligns with CWE-416, which specifically addresses use-after-free conditions in software implementations, and demonstrates how improper memory management can create persistent security risks in complex applications like web browsers. The attack pattern follows typical exploit chains identified in the MITRE ATT&CK framework under the technique of "Exploitation for Privilege Escalation" and "Command and Control" activities, as attackers can leverage such flaws to establish persistent access or execute malicious payloads. Organizations should prioritize immediate patching of affected Chrome installations to prevent exploitation, as the vulnerability represents a well-known attack vector that has been actively exploited in the wild. The remediation strategy involves upgrading to Chrome version 18.0.1025.151 or later, which includes memory management fixes specifically addressing the focus handling mechanisms that were susceptible to this use-after-free condition.