CVE-2017-5027 in Chrome
Summary
by MITRE
Blink in Google Chrome prior to 56.0.2924.76 for Linux, Windows and Mac, and 56.0.2924.87 for Android, failed to properly enforce unsafe-inline content security policy, which allowed a remote attacker to bypass content security policy via a crafted HTML page.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 08/28/2024
The vulnerability identified as CVE-2017-5027 represents a critical security flaw in the Blink rendering engine used by Google Chrome across multiple platforms including Linux, Windows, Mac, and Android. This issue stems from an improper implementation of content security policy enforcement mechanisms that directly undermines the browser's ability to protect users from malicious content injection attacks. The vulnerability specifically affects Chrome versions prior to 56.0.2924.76 for desktop platforms and 56.0.2924.87 for Android, making it a significant concern for users running these outdated browser versions.
The technical root cause of this vulnerability lies in the rendering engine's failure to properly validate and enforce content security policy directives, particularly those related to unsafe-inline content. Content security policy serves as a critical web security mechanism designed to prevent a wide range of attacks including cross-site scripting, data injection, and other code injection vulnerabilities by restricting the sources from which content can be loaded. When the browser fails to enforce unsafe-inline policies correctly, it creates a pathway for attackers to bypass these protective measures and inject malicious code into web pages. This flaw allows remote attackers to craft specially designed HTML pages that can circumvent the intended security boundaries established by content security policy headers.
The operational impact of this vulnerability extends beyond simple bypassing of security controls, as it fundamentally undermines the trust model that web browsers establish with users. Attackers can exploit this weakness to execute malicious scripts in contexts where they would normally be blocked, potentially leading to session hijacking, credential theft, data exfiltration, or full system compromise. The vulnerability's cross-platform nature means that users across different operating systems are equally at risk, making it a particularly dangerous flaw that affects a broad user base. Additionally, the fact that this affects both desktop and mobile versions of Chrome creates multiple attack vectors for threat actors targeting different device types.
From a cybersecurity perspective, this vulnerability aligns with CWE-16 (Configuration) and relates to the broader category of security misconfigurations that can lead to privilege escalation and unauthorized access. The ATT&CK framework would categorize this as a technique involving "Web Protocols and Services" with potential connections to "Command and Scripting Interpreter" and "Exploitation for Client Execution" tactics. Organizations and individuals should immediately update to the patched versions of Chrome to mitigate this risk, as the vulnerability can be exploited remotely without user interaction. The remediation process involves updating to Chrome version 56.0.2924.76 or later for desktop platforms and 56.0.2924.87 or later for Android, ensuring that the browser's content security policy enforcement mechanisms function as intended to prevent unauthorized code execution.
This vulnerability demonstrates the critical importance of proper security policy enforcement in web browsers and highlights the potential consequences of insufficient validation of security controls. The flaw serves as a reminder that even seemingly minor implementation errors in core security mechanisms can have significant operational impacts, potentially allowing attackers to bypass multiple layers of web security protections that users rely upon for their online safety.