CVE-2015-7643 in Flash Player
Summary
by MITRE
Use-after-free vulnerability in Adobe Flash Player before 18.0.0.252 and 19.x before 19.0.0.207 on Windows and OS X and before 11.2.202.535 on Linux, Adobe AIR before 19.0.0.213, Adobe AIR SDK before 19.0.0.213, and Adobe AIR SDK & Compiler before 19.0.0.213 allows attackers to execute arbitrary code via a Video object with a crafted deblocking property, a different vulnerability than CVE-2015-7629, CVE-2015-7631, and CVE-2015-7644.
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Analysis
by VulDB Data Team • 06/21/2022
The CVE-2015-7643 vulnerability represents a critical use-after-free flaw in Adobe Flash Player and related software components that has significant implications for system security. This vulnerability specifically affects multiple versions of Adobe Flash Player across different operating systems including Windows and OS X, with the affected versions being prior to 18.0.0.252 and 19.x before 19.0.0.207, alongside Linux versions before 11.2.202.535. Additionally, Adobe AIR and its associated SDK components were impacted, with affected versions prior to 19.0.0.213. The vulnerability stems from improper memory management during the handling of Video objects, particularly when processing a crafted deblocking property that triggers the use-after-free condition. This type of vulnerability falls under CWE-416 which specifically addresses the use of freed memory, making it a classic example of memory safety issues in software development. The attack vector involves an attacker crafting malicious Video objects with specific deblocking properties that, when processed by the vulnerable Flash Player, cause memory to be freed but subsequently accessed, creating a scenario where arbitrary code execution becomes possible.
The technical implementation of this vulnerability occurs within the Flash Player's video processing pipeline where Video objects are manipulated with specially crafted deblocking parameters. When the Flash Player encounters such malformed objects, it fails to properly validate the memory references, leading to a situation where freed memory locations are accessed after the original allocation has been released. This memory management failure creates a predictable pattern that attackers can exploit to inject and execute malicious code within the context of the Flash Player process. The vulnerability is particularly dangerous because it allows for privilege escalation and code execution without requiring user interaction beyond visiting a malicious webpage or opening a specially crafted file. The exploitation process typically involves crafting a malicious SWF file that, when loaded by the vulnerable Flash Player, triggers the memory corruption through the Video object manipulation with the crafted deblocking property. The specific nature of this vulnerability places it within the ATT&CK framework under technique T1059.007 for command and scripting interpreter, as successful exploitation would enable attackers to execute arbitrary commands within the compromised system.
The operational impact of CVE-2015-7643 extends far beyond simple memory corruption, as it provides attackers with a pathway to achieve full system compromise through remote code execution. Organizations that had not updated their Flash Player installations were particularly vulnerable, as the attack could be delivered through web browsers or any application that embedded Flash content. The vulnerability's presence in multiple software components including Adobe AIR and AIR SDK meant that the attack surface was significantly broadened, affecting not just web-based applications but also desktop applications built using these frameworks. The use-after-free condition creates a reliable exploitation opportunity that can be leveraged for persistent access, data exfiltration, and further attack progression within network environments. Security professionals noted that the vulnerability was particularly concerning because it could be exploited in zero-day scenarios before patches were widely deployed, making it a prime target for advanced persistent threat actors. The vulnerability's classification as a remote code execution flaw aligns with the ATT&CK technique T1203 for exploitation for privilege escalation, as the code execution would typically occur in the context of the Flash Player process which often runs with elevated privileges. Organizations that relied heavily on Flash-based content for business applications or web services faced critical exposure, as the vulnerability could be exploited through standard web browsing activities without requiring any special user interaction or privilege escalation beyond the initial compromise.
Mitigation strategies for CVE-2015-7643 focused primarily on immediate patching and software updates, as Adobe released security updates to address the vulnerability in versions 18.0.0.252, 19.0.0.207, and 19.0.0.213 for respective components. System administrators were advised to implement immediate patch management procedures to update all affected Flash Player installations across their networks, with particular attention to legacy systems that might not receive regular updates. Network security controls including web proxies and content filtering systems were enhanced to block Flash content or restrict access to known malicious domains that might host exploit code. The vulnerability highlighted the importance of application whitelisting and sandboxing techniques, as these approaches would have limited the impact of successful exploitation attempts. Security monitoring was strengthened to detect unusual Flash Player behavior or attempts to access freed memory locations, with intrusion detection systems configured to alert on suspicious patterns in network traffic or system calls. Organizations were also encouraged to implement the principle of least privilege for Flash Player usage, restricting its execution to only trusted environments where necessary. The vulnerability underscored the critical importance of maintaining up-to-date security patches and the dangers of running outdated software components, as the attack surface remained significant for organizations that delayed patch deployment. Incident response procedures were updated to include specific guidance for handling Flash Player-based exploits, with security teams trained to recognize the symptoms of use-after-free vulnerabilities and respond appropriately to containment and remediation efforts.