CVE-2016-1697 in Chrome
Summary
by MITRE
The FrameLoader::startLoad function in WebKit/Source/core/loader/FrameLoader.cpp in Blink, as used in Google Chrome before 51.0.2704.79, does not prevent frame navigations during DocumentLoader detach operations, which allows remote attackers to bypass the Same Origin Policy via crafted JavaScript code.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 08/23/2022
The vulnerability identified as CVE-2016-1697 resides within the Blink rendering engine's FrameLoader component, specifically in the FrameLoader::startLoad function located at WebKit/Source/core/loader/FrameLoader.cpp. This flaw represents a critical security issue that affects Google Chrome versions prior to 51.0.2704.79, where the browser's implementation fails to properly enforce security boundaries during document lifecycle transitions. The vulnerability stems from insufficient validation mechanisms that should prevent frame navigation operations while DocumentLoader objects are being detached from the rendering context, creating a window of opportunity for malicious actors to exploit.
The technical implementation flaw occurs when the DocumentLoader undergoes detachment operations, which typically happen during navigation or document replacement scenarios. During these transitional states, the FrameLoader::startLoad function does not adequately validate whether frame navigation requests should be permitted, allowing attackers to inject malicious JavaScript code that can manipulate frame loading behavior. This creates a race condition where navigation operations can proceed even when the underlying document context is in an unstable state, effectively undermining the browser's security model.
The operational impact of this vulnerability is significant as it enables remote attackers to bypass the fundamental Same Origin Policy that protects web applications from cross-origin attacks. This policy enforcement mechanism is crucial for preventing malicious websites from accessing data from different origins, and its circumvention allows attackers to perform unauthorized operations across domains. The vulnerability specifically enables attackers to manipulate frame navigation sequences in ways that could lead to data exfiltration, cross-site scripting attacks, or other malicious activities that exploit the trust relationships between different web origins.
This vulnerability maps to CWE-284, which addresses inadequate access control mechanisms, and aligns with ATT&CK techniques related to privilege escalation and credential access. The flaw essentially creates a pathway for attackers to escalate their privileges within the browser sandbox by exploiting the timing gap between document detachment and frame loading operations. Organizations should immediately update to Chrome version 51.0.2704.79 or later, which implements proper validation checks in the FrameLoader::startLoad function to prevent frame navigation during DocumentLoader detach operations. Additional mitigations include implementing Content Security Policy headers, disabling unnecessary frame loading capabilities, and maintaining regular browser updates to address similar vulnerabilities in the Blink rendering engine's security architecture.