CVE-2017-3071 in Flash Player
Summary
by MITRE
Adobe Flash Player versions 25.0.0.148 and earlier have an exploitable use after free vulnerability when masking display objects. Successful exploitation could lead to arbitrary code execution.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 12/06/2022
Adobe Flash Player contained a critical use after free vulnerability in version 25.0.0.148 and earlier that arose during the handling of display object masking operations. This flaw occurred when the Flash Player attempted to free memory associated with display objects while still referencing them in masking contexts, creating a scenario where malicious actors could exploit the dangling pointer to execute arbitrary code. The vulnerability was classified as a use after free condition under CWE-416, representing a fundamental memory safety issue where freed memory was accessed beyond its intended lifecycle. The technical implementation involved the Flash Player's rendering engine failing to properly track reference counts for display objects during masking operations, allowing attackers to manipulate the memory layout and overwrite critical function pointers or code segments. This particular vulnerability exploited the complex interaction between Flash's display list management and its garbage collection mechanisms, where the masking process created a race condition that could be leveraged to achieve remote code execution. The operational impact was severe given Flash Player's widespread deployment across enterprise environments and end-user systems, making this vulnerability particularly dangerous for targeted attacks. Attackers could craft malicious SWF files that, when loaded in vulnerable Flash Player versions, would trigger the use after free condition through carefully constructed display object hierarchies and masking operations. This vulnerability aligned with ATT&CK technique T1059.007 for command and control through Flash-based malware delivery, and T1203 for exploitation of remote services through web browsers. The exploitation process typically involved creating a memory corruption scenario that could be chained with other techniques to bypass modern exploit mitigations such as ASLR and DEP. Organizations running vulnerable versions faced significant risk of compromise, as the vulnerability could be triggered through web browsing activities without user interaction, making it particularly effective for drive-by download attacks. The flaw demonstrated the inherent risks of complex multimedia frameworks in handling memory management and object lifecycle management, where the interaction between different subsystems created unexpected attack surfaces. Security researchers noted that the vulnerability required sophisticated exploitation techniques due to modern memory protection mechanisms, but the widespread deployment of vulnerable Flash Player versions made it a high-priority target for attackers. The issue was ultimately addressed through Adobe's security patches that corrected the memory management logic in the display object handling code, though the broader implications highlighted the need for better memory safety practices in legacy multimedia frameworks. This vulnerability served as a prime example of how legacy software components could harbor critical security flaws that remained undetected for extended periods, particularly in complex systems with extensive codebases and multiple interacting components. The remediation efforts required comprehensive system updates across enterprise environments, as Flash Player was deeply integrated into many web applications and content delivery systems. The incident underscored the importance of continuous security assessment and the challenges of maintaining security in aging software ecosystems where patches may not be promptly deployed across all user bases. Organizations needed to implement comprehensive patch management strategies and consider the broader security implications of legacy multimedia technologies in their overall security posture. The vulnerability also highlighted the need for better automated detection mechanisms that could identify potentially vulnerable Flash content in enterprise networks, as the exploitation could occur without user awareness or explicit interaction with malicious content.