CVE-2016-20060 in Hotspot Shield
Summary
by MITRE • 04/04/2026
Hotspot Shield 6.0.3 contains an unquoted service path vulnerability in the hshld service binary that allows local attackers to escalate privileges by injecting malicious executables. Attackers can place executable files in the service path and upon service restart or system reboot, the malicious code executes with LocalSystem privileges.
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Analysis
by VulDB Data Team • 04/04/2026
The vulnerability identified as CVE-2016-20060 represents a critical privilege escalation flaw within Hotspot Shield version 6.0.3, specifically targeting the hshld service binary. This issue stems from improper service path configuration that creates an exploitable condition where the service does not properly quote the executable path, allowing attackers to manipulate the service execution flow. The vulnerability is classified under CWE-428, which addresses the improper handling of unquoted service paths, making it a well-documented weakness in Windows service management.
The technical implementation of this flaw occurs when the hshld service binary is installed without proper quotation of the executable path in the Windows service registry. This configuration allows any local user to place malicious executables in directories along the service path without requiring elevated privileges. When the service restarts or the system reboots, the Windows service manager executes the malicious binary from the compromised path, resulting in code execution with LocalSystem privileges. This represents a classic privilege escalation vector that directly violates the principle of least privilege and enables attackers to gain elevated system access.
From an operational perspective, this vulnerability poses significant risks to organizations using Hotspot Shield 6.0.3, as local attackers with basic user privileges can exploit this flaw to achieve system-level control. The attack requires no special network access or external exploitation, making it particularly dangerous as it can be leveraged by malicious insiders or compromised low-privilege accounts. The persistence mechanism provided by this vulnerability allows attackers to maintain access across system reboots, creating a stable foothold for further exploitation and data exfiltration activities.
The exploitation of this vulnerability aligns with several tactics described in the MITRE ATT&CK framework, particularly focusing on privilege escalation techniques such as service execution and persistence mechanisms. The vulnerability enables attackers to move from initial access to elevated privileges without requiring additional attack vectors, making it a valuable target for adversaries seeking to establish persistent access to compromised systems. Organizations should consider this vulnerability in their threat modeling and incident response planning, as it represents a straightforward path to system compromise that can be exploited by both skilled and less sophisticated attackers.
Mitigation strategies for CVE-2016-20060 should prioritize immediate patching of the Hotspot Shield software to the latest version that addresses the unquoted service path issue. System administrators should also implement proper service path quoting through registry modifications or service reinstallation processes. Additional defensive measures include monitoring service binary locations for unauthorized modifications, implementing application whitelisting policies to restrict execution of unauthorized binaries, and conducting regular security audits to identify other potentially vulnerable services. The vulnerability highlights the importance of secure service configuration practices and demonstrates how seemingly minor configuration errors can create significant security risks.