CVE-2013-0078 in Windows Defender
Summary
by MITRE
The Microsoft Antimalware Client in Windows Defender on Windows 8 and Windows RT uses an incorrect pathname for MsMpEng.exe, which allows local users to gain privileges via a crafted application, aka "Microsoft Antimalware Improper Pathname Vulnerability."
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Analysis
by VulDB Data Team • 12/28/2024
The vulnerability described in CVE-2013-0078 represents a critical privilege escalation flaw within Microsoft Windows Defender's antimalware client implementation. This issue specifically affects Windows 8 and Windows RT operating systems where the Microsoft Antimalware Client component fails to properly validate pathname references when executing MsMpEng.exe processes. The improper pathname handling creates a security gap that malicious local users can exploit to elevate their privileges from standard user level to system level access.
The technical root cause of this vulnerability stems from insufficient input validation within the Windows Defender client architecture. When the antimalware client processes certain applications or system calls, it incorrectly resolves the pathname for MsMpEng.exe, which is the core malware scanning engine process. This incorrect pathname resolution allows attackers to manipulate the execution flow by placing a malicious executable with the same name in a location that gets prioritized during the path resolution process. The vulnerability manifests as a path traversal or path injection issue that directly violates secure coding practices and security by design principles.
From an operational impact perspective, this vulnerability provides local attackers with a straightforward method to achieve system-level privileges without requiring external network access or complex exploitation techniques. The attack vector is particularly concerning because it leverages legitimate system components and processes, making detection more difficult for security monitoring systems. Once successfully exploited, attackers can gain complete control over the affected system, potentially leading to data theft, persistent backdoor installation, or further network propagation. The vulnerability affects the fundamental security model of Windows 8 and RT systems, undermining the principle of least privilege that is central to operating system security.
The exploitation of this vulnerability aligns with several attack patterns documented in the MITRE ATT&CK framework, particularly those related to privilege escalation and persistence mechanisms. The flaw can be categorized under CWE-22 Path Traversal and CWE-78 Improper Neutralization of Special Elements used in an OS Command, both of which are well-established weakness categories that demonstrate the importance of proper input validation and secure path handling. Organizations should implement immediate mitigations including applying the relevant Microsoft security updates, implementing strict file system permissions, and monitoring for unusual MsMpEng.exe process execution patterns. Additionally, system administrators should consider implementing application whitelisting policies and regular security audits to detect potential exploitation attempts. The vulnerability underscores the critical need for robust secure coding practices and proper privilege management within security software components to prevent such flaws from creating exploitable conditions in operating system environments.