CVE-2018-18340 in Chrome
Summary
by MITRE
Incorrect object lifecycle in MediaRecorder in Google Chrome prior to 71.0.3578.80 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page.
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Analysis
by VulDB Data Team • 06/18/2023
The vulnerability identified as CVE-2018-18340 represents a critical heap corruption issue within Google Chrome's MediaRecorder implementation prior to version 71.0.3578.80. This flaw exists within the object lifecycle management of the MediaRecorder API, which is designed to capture media streams from web applications. The vulnerability stems from improper handling of object destruction and memory management when processing media recording operations, creating opportunities for malicious actors to manipulate heap memory structures through carefully crafted web content.
The technical exploitation of this vulnerability occurs when a remote attacker crafts a malicious HTML page that triggers specific conditions within the MediaRecorder API. The flaw manifests during the object lifecycle management where the MediaRecorder instance fails to properly release memory resources when transitioning between different states or when encountering exceptional conditions. This improper memory management creates heap corruption vulnerabilities that can be leveraged to execute arbitrary code on the target system. The vulnerability specifically targets the interaction between the MediaRecorder API and the underlying memory allocation mechanisms, where objects may be freed while still referenced or where memory reuse occurs without proper validation.
From an operational impact perspective, this vulnerability poses significant risks to users of affected Chrome versions as it enables remote code execution through web-based attacks. The heap corruption allows attackers to potentially overwrite critical memory locations, manipulate program execution flow, and ultimately gain control over the affected system. The attack vector requires only a user to visit a malicious webpage, making it particularly dangerous for widespread exploitation. The vulnerability affects the core security model of the browser by allowing attackers to bypass memory protection mechanisms that should prevent such corruption scenarios.
The flaw aligns with CWE-122 (Heap Overflow) and CWE-415 (Double Free) categories within the Common Weakness Enumeration framework, representing improper memory management practices in the MediaRecorder component. From an ATT&CK framework perspective, this vulnerability maps to T1059.007 (Command and Scripting Interpreter: JavaScript) and T1078.004 (Valid Accounts: Cloud Accounts) as attackers can leverage JavaScript execution within the browser context to exploit the heap corruption. The vulnerability also relates to T1547.001 (Registry Run Keys and Startup Folder) through potential persistence mechanisms that could be established via successful exploitation.
Mitigation strategies for this vulnerability require immediate patching of Chrome browsers to version 71.0.3578.80 or later, which implements proper object lifecycle management for MediaRecorder instances. Organizations should also implement network-based security controls including web application firewalls and content filtering systems that can detect and block malicious HTML content. Browser hardening measures such as disabling unnecessary media APIs, implementing strict content security policies, and using sandboxing mechanisms can provide additional protection layers. Regular security assessments and vulnerability scanning should be conducted to identify similar memory management issues in other browser components or web applications that might be susceptible to similar heap corruption attacks.