CVE-2017-5085 in Chrome
Summary
by MITRE
Inappropriate implementation in Bookmarks in Google Chrome prior to 59 for iOS allowed a remote attacker who convinced the user to perform certain operations to run JavaScript on chrome:// pages via a crafted bookmark.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 01/05/2023
The vulnerability identified as CVE-2017-5085 represents a critical security flaw in Google Chrome versions prior to 59 for iOS platforms. This issue stems from an inadequate implementation of the bookmarks functionality that creates a pathway for remote code execution through maliciously crafted bookmark entries. The flaw specifically affects the handling of chrome:// URLs within the bookmark system, which are typically reserved for internal browser functionality and should be protected from external manipulation.
The technical implementation error occurs within Chrome's bookmark processing mechanism where the browser fails to properly sanitize or validate bookmark entries that reference chrome:// protocol URLs. When a user encounters a maliciously crafted bookmark containing JavaScript within a chrome:// page reference, the browser's insufficient input validation allows arbitrary script execution to occur. This vulnerability operates at the intersection of improper input validation and privilege escalation, as it leverages the trusted chrome:// protocol to execute malicious code in a privileged context.
From an operational perspective, this vulnerability creates a significant risk for users who may inadvertently interact with malicious bookmarks distributed through phishing campaigns, compromised websites, or social engineering attacks. The attack requires user interaction to perform specific operations, making it a client-side exploit that relies on user behavior rather than automated exploitation. However, the impact is severe as successful exploitation can lead to complete browser compromise, potential data theft, and further lateral movement within the user's system environment.
The vulnerability aligns with CWE-79 which describes improper neutralization of input during web page generation, specifically in the context of bookmark handling and URL processing. This weakness creates an environment where attacker-controlled input can be executed within privileged browser contexts, potentially enabling techniques described in the ATT&CK framework under T1059 for command and scripting interpreter execution. The threat landscape for this vulnerability includes advanced persistent threat actors who may leverage it as part of multi-stage attack campaigns targeting iOS users of the affected Chrome versions.
Mitigation strategies should focus on immediate remediation through Chrome version updates to 59 or later, which address the bookmark validation implementation. Organizations should also implement user education programs to raise awareness about suspicious bookmark entries and encourage safe browsing practices. Browser security policies should include restrictions on bookmark manipulation and monitoring for unusual bookmark creation patterns. Additionally, network-level security controls such as web application firewalls and content filtering systems can help detect and block malicious bookmark content before it reaches user systems. The fix implemented in Chrome 59 addresses the core issue by strengthening input validation and ensuring proper sanitization of bookmark entries that reference internal chrome:// URLs, thereby preventing the execution of unauthorized JavaScript code within privileged browser contexts.