CVE-2019-13684 in Chrome
Summary
by MITRE
Inappropriate implementation in JavaScript in Google Chrome prior to 72.0.3626.81 allowed a remote attacker to leak cross-origin data via a crafted HTML page.
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Analysis
by VulDB Data Team • 02/27/2024
The vulnerability identified as CVE-2019-13684 represents a significant security flaw in Google Chrome's JavaScript implementation that existed prior to version 72.0.3626.81. This issue falls under the category of cross-origin data leakage, where an attacker can exploit the browser's JavaScript engine to access information that should be restricted due to cross-origin policies. The vulnerability specifically manifests through crafted HTML pages that manipulate the browser's security boundaries, potentially exposing sensitive data from different origins. This type of flaw directly undermines the fundamental security model that browsers implement to isolate web content and protect user data from unauthorized access.
The technical implementation flaw lies in how Chrome's JavaScript engine handles certain cross-origin operations, allowing malicious actors to bypass the same-origin policy that normally prevents scripts from accessing resources from different domains. This weakness enables attackers to craft HTML pages that can extract data from cross-origin sources through carefully constructed JavaScript code. The vulnerability operates at the intersection of browser security mechanisms and JavaScript execution, where the engine fails to properly enforce security boundaries when processing specific combinations of cross-origin requests and script execution contexts. The flaw is particularly concerning because it requires no user interaction beyond visiting a malicious webpage, making it a passive attack vector that can be exploited through drive-by downloads or compromised websites.
The operational impact of CVE-2019-13684 extends beyond simple data leakage, as it represents a potential pathway for more sophisticated attacks. Attackers could leverage this vulnerability to gather sensitive information from users' sessions, including cookies, authentication tokens, or other cross-origin data that should remain protected. The implications are particularly severe in environments where users interact with multiple domains or services, as the vulnerability could expose data from banking applications, social media accounts, or corporate intranets. This type of vulnerability directly violates the core security principle of isolation that browsers maintain between different origins, potentially enabling session hijacking, credential theft, or privilege escalation attacks. The vulnerability's exploitation capability aligns with ATT&CK technique T1071.001 for application layer protocol usage and T1566 for credential harvesting through social engineering.
Security mitigations for CVE-2019-13684 primarily focus on updating to Chrome version 72.0.3626.81 or later, which includes patches that properly enforce cross-origin restrictions in JavaScript execution contexts. Organizations should implement comprehensive browser update policies to ensure all users are running patched versions of Chrome. Additional protective measures include implementing content security policies that restrict cross-origin resource access, monitoring for suspicious cross-origin requests in web application logs, and educating users about the risks of visiting untrusted websites. The vulnerability's classification as an improper implementation issue aligns with CWE-691, which addresses inadequate protection of a resource during execution. Browser vendors should also consider implementing additional sandboxing mechanisms and stricter JavaScript security controls to prevent similar vulnerabilities from emerging in the future. Organizations may also want to deploy web application firewalls or security monitoring tools that can detect and block suspicious cross-origin data access patterns that could indicate exploitation attempts.