CVE-2015-5672 in Fate
Summary
by MITRE
TYPE-MOON Fate/stay night, Fate/hollow ataraxia, Witch on the Holy Night, and Fate/stay night + hollow ataraxia set allow remote attackers to execute arbitrary OS commands via crafted saved data.
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Analysis
by VulDB Data Team • 03/08/2018
The vulnerability identified as CVE-2015-5672 represents a critical remote code execution flaw affecting multiple titles in the TYPE-MOON Fate franchise including Fate/stay night, Fate/hollow ataraxia, Witch on the Holy Night, and the combined Fate/stay night + hollow ataraxia set. This security weakness stems from inadequate input validation within the game's saved data handling mechanisms, creating an avenue for malicious actors to inject and execute arbitrary operating system commands on affected systems. The flaw specifically manifests when the games process crafted saved game files that contain malicious command sequences, allowing attackers to leverage the game's file processing functionality as a vector for system compromise.
The technical implementation of this vulnerability resides in the games' deserialization and data parsing routines where saved game data is loaded and interpreted without proper sanitization of user-controlled inputs. When these games process saved data files containing specially crafted command sequences, the parsing logic fails to properly validate or escape the input, leading to command injection attacks. This vulnerability directly maps to CWE-77, known as "Command Injection," which is classified as a critical weakness in software security where user-supplied data is directly incorporated into system commands without proper validation or sanitization. The flaw essentially allows attackers to execute arbitrary commands with the privileges of the user running the affected game, potentially leading to complete system compromise.
The operational impact of CVE-2015-5672 extends beyond simple remote code execution, creating a significant threat vector for attackers seeking to exploit gaming systems. Since these games are commonly installed on personal computers and gaming consoles, the attack surface is extensive and includes both individual users and potentially corporate environments where such games might be present. The vulnerability enables attackers to perform actions such as installing malware, accessing sensitive system information, modifying or deleting files, and potentially establishing persistent backdoors. This type of vulnerability aligns with ATT&CK technique T1059.001, which covers command and scripting interpreter, where adversaries use legitimate system tools to execute malicious commands, and T1078, which addresses valid accounts, as the attack can potentially be performed through legitimate user accounts running the games. The remote nature of the attack means that exploitation can occur without physical access to the target system, making it particularly dangerous for gaming environments.
Mitigation strategies for CVE-2015-5672 should focus on both immediate protective measures and long-term architectural improvements. The most effective immediate solution involves applying official patches and updates released by TYPE-MOON or the game distributors to address the input validation flaws in the saved data handling routines. Users should also implement strict file access controls, ensuring that saved game files are only created and modified by trusted sources, and that the games are run with minimal privileges. Network-level protections including firewalls and intrusion detection systems can help monitor for suspicious network activity related to game file transfers. Additionally, implementing application whitelisting policies that restrict execution of unauthorized code can prevent exploitation attempts. Organizations should also consider implementing regular security assessments of gaming environments and establishing secure coding practices that emphasize input validation and sanitization to prevent similar vulnerabilities from emerging in future software releases.