CVE-2020-1132 in Windows
Summary
by MITRE
An elevation of privilege vulnerability exists when Windows Error Reporting manager improperly handles file and folder links, aka 'Windows Error Reporting Manager Elevation of Privilege Vulnerability'.
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Analysis
by VulDB Data Team • 10/17/2020
The vulnerability identified as CVE-2020-1132 represents a critical elevation of privilege flaw within the Windows Error Reporting manager component of Microsoft Windows operating systems. This vulnerability stems from improper handling of file and folder links by the error reporting manager, which allows malicious actors to escalate their privileges from standard user level to system level access. The flaw specifically affects the way Windows Error Reporting processes symbolic links and hard links within file system structures, creating an exploitable condition that can be leveraged by attackers to execute arbitrary code with elevated privileges. The vulnerability impacts multiple Windows versions including Windows 10, Windows Server 2016, and Windows Server 2019, making it a widespread concern for enterprise environments. According to CWE-264, this vulnerability maps to permissions, privileges, and access control issues, specifically CWE-276 which deals with insecure default permissions, and CWE-787 which addresses out-of-bounds write conditions. The vulnerability aligns with ATT&CK technique T1068, which covers 'Exploitation for Privilege Escalation' and T1547.001, covering 'Registry Run Keys / Startup Folder' as attackers can leverage this flaw to establish persistence mechanisms.
The technical exploitation of CVE-2020-1132 occurs when a malicious user creates specially crafted symbolic links or hard links within the Windows Error Reporting directory structure. The error reporting manager, which typically runs with elevated privileges to collect crash information and system diagnostics, fails to properly validate the target paths of these links before processing them. This improper validation allows attackers to redirect the error reporting process to execute malicious code from arbitrary locations on the file system. The flaw essentially creates a path traversal condition where the error reporting manager follows links without adequate security checks, enabling attackers to bypass normal access controls and execute code with system-level privileges. Attackers can exploit this by placing malicious executables in locations that are accessed through the vulnerable link structures, effectively allowing them to escalate their privileges without requiring authentication or prior access to the system.
The operational impact of this vulnerability extends beyond simple privilege escalation, as it provides attackers with the ability to establish persistent access to compromised systems. Once an attacker achieves system-level privileges through this vulnerability, they can modify system files, install rootkits, disable security features, and exfiltrate sensitive data without detection. The vulnerability is particularly dangerous in enterprise environments where standard users may have access to systems that are not properly segmented or where the error reporting functionality is enabled for troubleshooting purposes. Organizations running affected Windows versions are at risk of complete system compromise, as the attacker can leverage this vulnerability to gain full administrative control over affected machines. The exploitability of this vulnerability is relatively straightforward, as it does not require complex conditions or specialized tools beyond basic file manipulation capabilities. The attack surface is further expanded because the Windows Error Reporting manager is typically enabled and running on most Windows installations, making this vulnerability readily exploitable across a wide range of systems.
Mitigation strategies for CVE-2020-1132 should focus on both immediate patching and operational security measures. Microsoft released security updates in May 2020 that address this vulnerability through proper validation of file and folder links within the Windows Error Reporting manager. Organizations should prioritize applying the relevant security patches immediately, particularly for systems that are exposed to untrusted users or external networks. Additionally, implementing strict file system permissions and access controls can help reduce the attack surface, particularly by restricting write access to directories used by the error reporting manager. Network segmentation and privilege separation practices should be enforced to limit the potential impact of exploitation. System administrators should monitor for unusual error reporting activity and implement endpoint detection and response solutions that can identify suspicious link creation or manipulation activities. The vulnerability also underscores the importance of maintaining current security practices, including regular system updates, vulnerability assessments, and security awareness training for personnel who may inadvertently create exploitable conditions through improper file handling practices. Organizations should also consider implementing application whitelisting policies that restrict execution of unauthorized binaries, particularly in system directories where the error reporting manager operates.