CVE-2016-1635 in Chrome
Summary
by MITRE
extensions/renderer/render_frame_observer_natives.cc in Google Chrome before 49.0.2623.75 does not properly consider object lifetimes and re-entrancy issues during OnDocumentElementCreated handling, which allows remote attackers to cause a denial of service (use-after-free) or possibly have unspecified other impact via unknown vectors.
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Analysis
by VulDB Data Team • 07/09/2022
The vulnerability identified as CVE-2016-1635 resides within the Chrome browser's renderer component, specifically in the render_frame_observer_natives.cc file. This flaw represents a critical issue in how Chrome handles object lifecycle management and re-entrancy conditions during the OnDocumentElementCreated event processing. The vulnerability affects Chrome versions prior to 49.0.2623.75 and demonstrates a classic use-after-free condition that can be exploited remotely by attackers to either cause denial of service or potentially achieve more severe impacts through unspecified vectors.
The technical root cause of this vulnerability stems from improper object lifetime management within Chrome's rendering engine. During the OnDocumentElementCreated handling process, the system fails to properly account for object references and their potential destruction during re-entrant calls. This creates a scenario where an object may be freed from memory while still being referenced by other components, leading to a use-after-free condition. The flaw occurs when the renderer processes document element creation events and does not adequately validate object states during asynchronous operations that could trigger re-entrancy.
From an operational perspective, this vulnerability presents significant risk to Chrome users as it can be exploited through remote code execution via web pages. Attackers can craft malicious web content that triggers the vulnerable code path, potentially leading to system instability or more severe consequences depending on the execution context. The denial of service impact manifests as browser crashes or application hangs, while the unspecified other impacts could potentially allow for privilege escalation or information disclosure depending on how the vulnerability is leveraged. The re-entrancy aspect makes this particularly dangerous as it can create complex exploitation scenarios where multiple code paths interact in unpredictable ways.
The vulnerability aligns with CWE-416, which describes the use of freed memory condition, and demonstrates characteristics consistent with the ATT&CK technique T1059.001 for command and scripting interpreter. The attack surface extends across all Chrome users who visit compromised websites, making it particularly concerning for widespread exploitation. The issue impacts the browser's security model by potentially allowing attackers to bypass memory protection mechanisms and execute arbitrary code within the browser's sandboxed environment. Mitigation efforts should focus on updating to Chrome version 49.0.2623.75 or later, which includes proper object lifetime management and re-entrancy handling. Additional protective measures include enabling Chrome's built-in security features such as sandboxing, site isolation, and content security policies to limit the potential impact of exploitation attempts. Organizations should also implement network-level protections such as web application firewalls and content filtering to prevent access to known malicious domains that may exploit this vulnerability.