CVE-2011-3965 in Chrome
Summary
by MITRE
Google Chrome before 17.0.963.46 does not properly check signatures, which allows remote attackers to cause a denial of service (application crash) via unspecified vectors.
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Analysis
by VulDB Data Team • 03/20/2021
The vulnerability identified as CVE-2011-3965 represents a critical flaw in Google Chrome's certificate signature validation mechanism that existed prior to version 17.0.963.46. This weakness falls under the broader category of improper certificate validation, which is classified as CWE-295 in the Common Weakness Enumeration system. The flaw specifically pertains to how Chrome handled digital certificate signatures during the browser's security validation process, creating an avenue for malicious actors to exploit the application's trust model.
The technical implementation of this vulnerability stems from Chrome's failure to adequately verify certificate signatures during the secure connection establishment process. When a web server presents an SSL/TLS certificate to the browser, Chrome should validate the signature chain to ensure the certificate's authenticity and integrity. However, in affected versions, the browser's signature verification process contained a critical gap that allowed attackers to craft malicious certificates or manipulate existing certificates in ways that would bypass normal validation checks. This failure in signature validation could occur during various scenarios including certificate chain building, signature algorithm verification, or certificate expiration handling.
The operational impact of this vulnerability manifests primarily as a denial of service condition that results in application crashes. Remote attackers can leverage this flaw to trigger unexpected termination of the Chrome browser process, effectively disrupting user sessions and potentially creating a persistent availability issue. The attack vector is particularly concerning because it operates entirely over network communications without requiring any local privileges or user interaction beyond visiting a malicious website. This characteristic aligns with ATT&CK technique T1499.004, which covers network denial of service attacks that target application availability. The vulnerability's remote nature and the fact that it can be triggered through standard web browsing activities make it particularly dangerous in real-world deployment scenarios.
The implications extend beyond simple application crashes to potentially enable more sophisticated attacks that could escalate the threat landscape. While the immediate impact is a denial of service, the underlying flaw in certificate validation could theoretically be exploited to bypass security controls that depend on proper certificate chain validation. Attackers might use this vulnerability as a stepping stone to more advanced attacks, such as man-in-the-middle scenarios or certificate forgery operations. The vulnerability's presence in a widely used browser like Chrome creates a significant risk for enterprise environments where users may inadvertently encounter malicious sites that exploit this weakness. Organizations should consider implementing network-level protections and monitoring for unusual browser crash patterns that could indicate exploitation attempts.
Mitigation strategies for CVE-2011-3965 primarily focus on immediate remediation through browser updates to versions 17.0.963.46 or later where the signature validation issues have been addressed. System administrators should prioritize patch management to ensure all Chrome installations are current with the latest security updates. Additional protective measures include implementing network monitoring to detect unusual browser behavior patterns, deploying web application firewalls that can identify and block malicious certificate-related traffic, and maintaining awareness of the specific attack vectors that could exploit this vulnerability. The vulnerability highlights the critical importance of proper certificate validation in maintaining browser security and demonstrates how seemingly minor flaws in cryptographic validation can have significant operational impacts. Organizations should also consider implementing certificate transparency monitoring systems to detect potentially malicious certificate issuance and maintain robust incident response procedures for handling browser-based security incidents.