CVE-2016-0996 in Flash Player
Summary
by MITRE
Use-after-free vulnerability in the setInterval method in Adobe Flash Player before 18.0.0.333 and 19.x through 21.x before 21.0.0.182 on Windows and OS X and before 11.2.202.577 on Linux, Adobe AIR before 21.0.0.176, Adobe AIR SDK before 21.0.0.176, and Adobe AIR SDK & Compiler before 21.0.0.176 allows attackers to execute arbitrary code via crafted arguments, a different vulnerability than CVE-2016-0987, CVE-2016-0988, CVE-2016-0990, CVE-2016-0991, CVE-2016-0994, CVE-2016-0995, CVE-2016-0997, CVE-2016-0998, CVE-2016-0999, and CVE-2016-1000.
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Analysis
by VulDB Data Team • 07/10/2022
The CVE-2016-0996 vulnerability represents a critical use-after-free flaw within Adobe Flash Player's setInterval method implementation across multiple platform versions. This vulnerability affects Flash Player versions prior to 18.0.0.333 for Windows and OS X, versions through 21.x before 21.0.0.182 for the same platforms, and Linux versions before 11.2.202.577, along with Adobe AIR and its SDK components. The flaw manifests when the setInterval function processes crafted arguments that trigger improper memory management, creating a scenario where freed memory locations can be accessed and potentially overwritten by malicious code. This particular vulnerability operates independently from several other related issues including CVE-2016-0987 through CVE-2016-1000, making it a distinct threat vector that requires separate mitigation strategies.
The technical exploitation of this vulnerability stems from improper memory deallocation handling within Flash Player's JavaScript engine integration. When the setInterval method processes specially crafted arguments, it can cause the application to free memory resources while maintaining references to those locations, creating a use-after-free condition. This memory management flaw allows attackers to manipulate the freed memory space and inject malicious code that executes with the privileges of the Flash Player process. The vulnerability is particularly dangerous because it can be triggered through web-based attacks without requiring user interaction, making it an ideal candidate for drive-by download scenarios. The exploit chain typically involves creating a specific memory layout that, when the setInterval function processes the crafted inputs, leads to the execution of arbitrary code in the context of the Flash Player application.
The operational impact of CVE-2016-0996 extends beyond simple code execution to encompass full system compromise capabilities when combined with other exploitation techniques. Attackers leveraging this vulnerability can bypass security controls such as sandboxing mechanisms that normally isolate Flash content from the underlying operating system. The vulnerability affects multiple operating systems including Windows and OS X platforms, where it can be exploited to gain elevated privileges and execute malicious payloads with system-level access. In the context of enterprise environments, this vulnerability poses significant risk as Flash Player remains widely deployed across corporate networks, making it a prime target for advanced persistent threats. The vulnerability's presence in Adobe AIR and SDK components further amplifies its impact, as these tools are commonly used for developing and distributing applications that may inadvertently expose users to exploitation.
Mitigation strategies for CVE-2016-0996 primarily focus on immediate patch deployment and operational security measures. Organizations should prioritize updating all affected Flash Player installations to versions 18.0.0.333 or later for Windows and OS X, 21.0.0.182 or later for the same platforms, and 11.2.202.577 or later for Linux systems. Adobe AIR users must upgrade to version 21.0.0.176 or later to address the vulnerability in their runtime environment. Beyond patching, security teams should implement network-based controls such as web application firewalls that can detect and block malicious Flash content, particularly content that utilizes setInterval with suspicious parameter patterns. The vulnerability aligns with CWE-416, which specifically addresses use-after-free conditions in memory management, and maps to ATT&CK technique T1059.007 for scripting languages, as the exploit leverages JavaScript within Flash Player's execution environment. Additional protective measures include disabling Flash Player in web browsers, implementing strict content security policies, and monitoring for anomalous behavior patterns that may indicate exploitation attempts. Organizations should also consider implementing endpoint detection and response solutions that can identify memory corruption patterns associated with use-after-free vulnerabilities, as these tools can provide early warning capabilities for exploitation attempts.