CVE-2016-0999 in Flash Player
Summary
by MITRE
Use-after-free vulnerability 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 unspecified vectors, a different vulnerability than CVE-2016-0987, CVE-2016-0988, CVE-2016-0990, CVE-2016-0991, CVE-2016-0994, CVE-2016-0995, CVE-2016-0996, CVE-2016-0997, CVE-2016-0998, and CVE-2016-1000.
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Analysis
by VulDB Data Team • 02/03/2025
The CVE-2016-0999 vulnerability represents a critical use-after-free flaw in Adobe Flash Player and related software components that affected multiple platform versions from 2016. This vulnerability falls under the common weakness enumeration CWE-416 which specifically addresses use-after-free conditions where memory is accessed after it has been freed, creating opportunities for memory corruption attacks. The flaw existed across Windows and macOS platforms in Flash Player versions prior to 18.0.0.333 and 19.x through 21.x before 21.0.0.182, while Linux versions were impacted until 11.2.202.577. Additionally, Adobe AIR and its SDK components were vulnerable until version 21.0.0.176, making this a widespread issue affecting the entire Adobe runtime ecosystem.
The technical exploitation of this vulnerability occurs when an attacker crafts malicious Flash content that triggers a specific memory management scenario where a freed memory block is accessed after it has been reallocated for other purposes. This particular use-after-free condition allows attackers to manipulate memory layout and potentially control program execution flow through carefully constructed payload delivery mechanisms. The vulnerability differs from several other related CVEs in the same year, indicating that while multiple flaws were present in the Flash Player codebase, this specific issue had unique triggering conditions and exploitation pathways that required distinct defensive approaches. The attack vectors remain unspecified in the public description, which is typical for zero-day vulnerabilities where attackers have not yet fully disclosed their methods, but the underlying memory corruption mechanism follows established patterns of heap-based exploitation techniques.
Operationally, this vulnerability posed significant risks to enterprise environments and individual users who relied on Flash Player for web content delivery. The use-after-free condition could be exploited through web browsers or other applications that embedded Flash content, potentially allowing attackers to execute arbitrary code with the privileges of the user running the vulnerable software. The impact extended beyond simple code execution to include potential privilege escalation scenarios, as attackers could leverage the memory corruption to gain elevated system access. This vulnerability was particularly dangerous because Flash Player was widely deployed across various platforms and applications, creating numerous potential attack surfaces. Organizations that had not yet patched their systems were exposed to remote code execution risks, with attackers able to leverage this vulnerability to establish persistent access or deploy additional malware payloads.
Mitigation strategies for CVE-2016-0999 centered around immediate patch deployment, which was the primary recommended action for system administrators. Adobe released security updates that addressed the specific memory management issues within the Flash Player runtime and AIR components. Organizations should have implemented network-based controls to block Flash content delivery where possible, particularly for users who did not require Flash functionality. The vulnerability highlighted the importance of maintaining up-to-date software components and demonstrated the risks associated with legacy software that had not received security updates. Security monitoring became critical for detecting exploitation attempts, as attackers would likely attempt to leverage the vulnerability through malicious web content or email attachments containing crafted Flash files. The incident also underscored the need for application whitelisting and sandboxing techniques to limit the potential impact of such vulnerabilities, as outlined in the attack technique T1059.007 for command and scripting interpreter usage in the MITRE ATT&CK framework. System administrators should have implemented comprehensive patch management processes to ensure timely remediation of similar vulnerabilities in the future.