CVE-2002-0476 in Flash Player
Summary
by MITRE
Standalone Macromedia Flash Player 5.0 allows remote attackers to save arbitrary files and programs via a .SWF file containing the undocumented "save" FSCommand.
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Analysis
by VulDB Data Team • 06/19/2024
The vulnerability described in CVE-2002-0476 represents a critical security flaw in the standalone Macromedia Flash Player version 5.0 that enables remote code execution through maliciously crafted .SWF files. This vulnerability exploits an undocumented FSCommand function named "save" which allows attackers to manipulate the Flash Player's file system operations. The flaw exists within the player's handling of Flash commands that are intended for communication between the Flash content and the hosting application or operating system. When a vulnerable Flash Player encounters a .SWF file containing this specific FSCommand, it can be coerced into executing arbitrary file operations on the target system, potentially leading to unauthorized file creation, modification, or execution of programs.
The technical implementation of this vulnerability stems from the Flash Player's insufficient validation of FSCommand parameters and lack of proper access controls when processing external commands. The "save" FSCommand function was never officially documented or intended for public use, making it an unexpected attack surface that developers and security professionals did not anticipate. When the Flash Player processes this command, it bypasses normal file system security boundaries and can write files to arbitrary locations on the victim's system. This behavior violates fundamental security principles and represents a classic case of insufficient input validation and improper privilege management. The vulnerability specifically affects systems running the standalone Flash Player 5.0 and earlier versions, as later releases addressed this security gap through improved command validation mechanisms.
The operational impact of CVE-2002-0476 is severe and far-reaching, as it enables attackers to establish persistent footholds on compromised systems through automated file creation and program execution. Attackers can leverage this vulnerability to deliver malware payloads, create backdoors, or establish unauthorized access points within the target environment. The ability to save arbitrary files means that malicious actors can install trojans, keyloggers, or other persistent threats that can operate without user interaction. This vulnerability directly maps to attack techniques described in the MITRE ATT&CK framework under T1195 (Supply Chain Compromise) and T1059 (Command and Scripting Interpreter) categories, as it allows for command execution and file manipulation at the system level. The vulnerability also aligns with CWE-73 (External Control of File Name or Path) and CWE-22 (Improper Limitation of a Pathname to a Restricted Directory) which highlight the dangers of insufficient input validation in file system operations.
Mitigation strategies for this vulnerability require immediate patching of affected Flash Player installations and implementation of network-level controls to prevent access to potentially malicious .SWF content. Organizations should deploy web application firewalls and content filtering solutions that can identify and block suspicious Flash content before it reaches vulnerable systems. The recommended remediation includes upgrading to patched versions of Flash Player where the undocumented FSCommand functionality has been properly secured or removed. System administrators should also implement strict file system permissions and monitoring to detect unauthorized file creation activities. Additionally, security awareness training should emphasize the risks of executing untrusted Flash content, particularly in enterprise environments where users may inadvertently download and execute malicious .SWF files from untrusted sources. The vulnerability demonstrates the importance of proper input validation and access control mechanisms in preventing privilege escalation attacks, and serves as a historical example of how undocumented features can create unexpected security risks in software applications.