CVE-2016-1616 in Chrome
Summary
by MITRE
The CustomButton::AcceleratorPressed function in ui/views/controls/button/custom_button.cc in Google Chrome before 48.0.2564.82 allows remote attackers to spoof URLs via vectors involving an unfocused custom button.
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Analysis
by VulDB Data Team • 07/06/2022
The vulnerability identified as CVE-2016-1616 resides within the Google Chrome browser's user interface component system, specifically in the CustomButton::AcceleratorPressed function located in ui/views/controls/button/custom_button.cc. This flaw represents a security issue that enables remote attackers to manipulate URL display behavior through crafted interactions with custom buttons within the browser interface. The vulnerability affects Chrome versions prior to 48.0.2564.82, making it a significant concern for users operating older browser versions. The technical implementation involves the browser's handling of accelerator key events when custom buttons are not currently focused, creating a potential vector for URL spoofing attacks.
The core technical flaw stems from improper handling of keyboard accelerator events in custom button components when those buttons lack focus. When a user interacts with an accelerator key while a custom button is unfocused, the system fails to properly validate or sanitize the URL context that might be displayed or manipulated during the button press operation. This behavior creates an opportunity for attackers to craft malicious web content that could exploit this condition to display misleading URLs or manipulate the URL bar display. The vulnerability specifically relates to how Chrome processes accelerator key events and manages focus states in its custom button controls, allowing for potential manipulation of the browser's URL display mechanism.
From an operational impact perspective, this vulnerability enables attackers to perform URL spoofing attacks that could deceive users into believing they are visiting legitimate websites when actually navigating to malicious destinations. The attack vector relies on users interacting with accelerator keys while a custom button is unfocused, which can occur in various browsing scenarios including when users quickly switch between tabs or when certain keyboard shortcuts are pressed. This type of attack could be particularly effective in phishing scenarios where attackers craft web pages designed to exploit this specific timing and focus condition. The vulnerability essentially allows for manipulation of the browser's URL display context without proper validation of the underlying URL source or legitimacy.
The technical implementation of this vulnerability aligns with common attack patterns found in software security contexts where improper state management and focus handling create opportunities for manipulation. This issue demonstrates how seemingly minor UI component flaws can create significant security implications when combined with user interaction patterns and keyboard event handling. The vulnerability is categorized under CWE-20, which deals with improper input validation, and represents a specific instance of how accelerator key handling can create security risks in GUI applications. From an ATT&CK framework perspective, this vulnerability could be leveraged as part of a phishing attack pattern under the T1566 technique category, specifically targeting credential theft through URL deception.
Mitigation strategies for CVE-2016-1616 primarily involve upgrading to Google Chrome version 48.0.2564.82 or later, which contains the necessary patches to address the focus handling and accelerator key processing issues. Additionally, users should implement browser security best practices including keeping their software updated, using security extensions, and being cautious when interacting with unfamiliar web content. Organizations should ensure their security policies include regular browser updates and monitoring for vulnerable software versions. The fix implemented by Google addresses the core issue by properly validating URL contexts during accelerator key events and ensuring consistent focus handling across custom button components. Security teams should also consider monitoring for similar patterns in other UI components that might exhibit similar focus and event handling vulnerabilities.