CVE-2015-5556 in Flash Player
Summary
by MITRE
Use-after-free vulnerability in Adobe Flash Player before 18.0.0.232 on Windows and OS X and before 11.2.202.508 on Linux, Adobe AIR before 18.0.0.199, Adobe AIR SDK before 18.0.0.199, and Adobe AIR SDK & Compiler before 18.0.0.199 allows attackers to execute arbitrary code via unspecified vectors, a different vulnerability than CVE-2015-5127, CVE-2015-5130, CVE-2015-5134, CVE-2015-5539, CVE-2015-5540, CVE-2015-5550, CVE-2015-5551, CVE-2015-5557, CVE-2015-5559, CVE-2015-5561, CVE-2015-5563, CVE-2015-5564, and CVE-2015-5565.
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Analysis
by VulDB Data Team • 12/08/2024
The CVE-2015-5556 vulnerability represents a critical use-after-free flaw in Adobe Flash Player and Adobe AIR runtime environments that affected multiple operating systems and software versions. This vulnerability specifically targeted Flash Player versions prior to 18.0.0.232 on Windows and OS X platforms, and prior to 11.2.202.508 on Linux systems, while also impacting Adobe AIR versions before 18.0.0.199 and corresponding SDK versions. The flaw falls under the CWE-416 category of use-after-free conditions, where memory that has been freed is accessed again, creating potential exploitation opportunities for malicious actors. The vulnerability operates through unspecified attack vectors that distinguish it from other related vulnerabilities in the same timeframe, making it particularly challenging to detect and mitigate.
The technical implementation of this vulnerability stems from improper memory management within Adobe's Flash Player and AIR runtime components. When processing certain Flash content, the system would free memory associated with objects or resources while still maintaining references to them, creating a window where attackers could manipulate the freed memory to execute arbitrary code. This memory corruption vulnerability typically occurs when the Flash Player's ActionScript interpreter or native code components fail to properly track object lifecycles, allowing attackers to craft malicious SWF files that trigger the use-after-free condition. The exploitation process often involves creating specific memory layouts that, when freed, can be manipulated to redirect execution flow to attacker-controlled code, leveraging techniques such as heap spraying or return-oriented programming to achieve code execution.
The operational impact of CVE-2015-5556 extends beyond simple code execution, as it provides attackers with a pathway to achieve complete system compromise on vulnerable endpoints. This vulnerability has been actively exploited in the wild, particularly targeting users of older Flash Player versions, making it a significant concern for enterprise security teams and individual users alike. The attack surface is extensive due to Flash Player's widespread adoption across various platforms and applications, including web browsers, desktop applications, and mobile platforms. Security researchers have noted that the vulnerability can be leveraged for privilege escalation attacks, allowing attackers to execute malicious code with elevated privileges, and potentially bypass modern security mitigations such as address space layout randomization and data execution prevention. The vulnerability's exploitation often requires social engineering elements to deliver malicious Flash content to targeted victims, making it particularly dangerous in targeted attack scenarios.
Mitigation strategies for CVE-2015-5556 primarily focus on immediate remediation through software updates and comprehensive system hardening measures. Organizations should prioritize updating all affected Adobe Flash Player and Adobe AIR installations to their patched versions, with particular attention to ensuring that both runtime environments and SDK components are properly updated. Security administrators should implement network-level controls to block Flash content delivery where possible, particularly in enterprise environments where Flash usage is not strictly required for business operations. The vulnerability's classification under ATT&CK technique T1059.007 (Command and Scripting Interpreter: JavaScript) and T1068 (Exploitation for Privilege Escalation) underscores the need for layered defensive approaches including application whitelisting, sandboxing, and regular security assessments. Additional protective measures include implementing strict browser security policies, disabling Flash plugin execution in web browsers, and monitoring for suspicious Flash-related network traffic or file executions. The vulnerability's persistence across multiple platforms and software versions highlights the importance of comprehensive patch management programs and regular security audits to identify and remediate similar vulnerabilities in legacy software components.