CVE-2014-7934 in Chrome
Summary
by MITRE
Use-after-free vulnerability in the DOM implementation in Blink, as used in Google Chrome before 40.0.2214.91, allows remote attackers to cause a denial of service or possibly have unspecified other impact via vectors related to unexpected absence of document data structures.
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Analysis
by VulDB Data Team • 03/06/2022
The vulnerability identified as CVE-2014-7934 represents a critical use-after-free flaw within the Document Object Model implementation of the Blink rendering engine, which was extensively utilized in Google Chrome versions prior to 40.0.2214.91. This type of vulnerability occurs when a program continues to reference memory locations that have already been freed, creating potential entry points for malicious exploitation. The issue specifically manifests within the DOM handling mechanisms where document data structures are improperly managed during certain operations, leading to unpredictable behavior when memory is accessed after being deallocated.
The technical exploitation of this vulnerability leverages the improper memory management practices within Blink's DOM implementation, particularly when processing web content that triggers the creation and destruction of document objects. Attackers can craft malicious web pages that manipulate the browser's DOM processing in such a way that memory references become invalid while still being accessed, creating conditions for arbitrary code execution or system instability. This vulnerability falls under the CWE-416 category of Use After Free, which is classified as a common weakness in software development practices where memory management is not properly enforced. The attack vector typically involves delivering malicious JavaScript content that triggers specific DOM operations causing the targeted memory structures to be freed while still being referenced elsewhere in the code execution path.
The operational impact of CVE-2014-7934 extends beyond simple denial of service scenarios, as the vulnerability could potentially enable remote code execution in certain circumstances, making it particularly dangerous for web-based attacks. When exploited, this flaw could allow attackers to execute arbitrary code on vulnerable systems with the privileges of the browser process, potentially leading to complete system compromise. The vulnerability's remote nature means that users need only visit a malicious website to be at risk, making it a significant threat vector for widespread exploitation. Organizations relying on older versions of Chrome for web browsing operations faced substantial risk exposure, as the vulnerability could be leveraged in drive-by download attacks or through compromised websites. The impact is particularly severe in enterprise environments where users may be browsing untrusted websites or where web applications are not properly sandboxed.
Mitigation strategies for this vulnerability primarily focus on immediate remediation through software updates, with Google releasing version 40.0.2214.91 to address the specific memory management issues in Blink's DOM implementation. System administrators should prioritize patching affected Chrome installations across all user devices, particularly in environments where users may encounter untrusted web content. Additional protective measures include implementing browser security policies that restrict access to potentially malicious websites, utilizing content security policies to limit script execution, and deploying network-based intrusion detection systems to monitor for exploitation attempts. The vulnerability also underscores the importance of proper memory management practices in browser engine development and highlights the need for comprehensive code review processes that specifically address use-after-free conditions. Organizations should consider implementing web application firewalls and browser isolation technologies as additional layers of protection against similar vulnerabilities, while also ensuring that their incident response procedures include specific protocols for addressing browser-based exploits. The remediation process should include thorough testing of patched versions to ensure that the memory management fixes do not introduce regressions in browser functionality, and regular security assessments should be conducted to identify potential similar weaknesses in other browser components or third-party libraries.