CVE-2020-37048: Iskysoft Privilege Escalation Vulnerability

CVE-2020-37048 Overview

CVE-2020-37048 is an unquoted service path vulnerability affecting Iskysoft Application Framework Service version 2.4.3.241. This flaw allows local users to potentially execute arbitrary code with elevated privileges by exploiting the improperly quoted executable path in the Windows service configuration. When the service starts, Windows parses the unquoted path and may execute a malicious binary placed strategically in the file system hierarchy, granting attackers SYSTEM-level privileges.

Critical Impact

Local privilege escalation vulnerability enabling attackers with local access to execute arbitrary code with elevated system permissions through malicious executable injection.

Affected Products

• Iskysoft Application Framework Service 2.4.3.241
• iSkysoft products utilizing the ISAppService component
• Windows systems with vulnerable Iskysoft software installed

Discovery Timeline

• 2026-02-01 - CVE CVE-2020-37048 published to NVD
• 2026-02-03 - Last updated in NVD database

Technical Details for CVE-2020-37048

Vulnerability Analysis

This vulnerability stems from CWE-428 (Unquoted Search Path or Element), a classic Windows privilege escalation weakness. When the Iskysoft Application Framework Service is installed, the service executable path is registered in the Windows Service Control Manager without proper quotation marks. Windows service paths containing spaces must be enclosed in quotes; otherwise, the operating system's path resolution algorithm may interpret portions of the path as separate arguments.

The vulnerability enables local privilege escalation because Windows services typically run under the SYSTEM account. An attacker with write access to specific directories in the file system hierarchy can place a malicious executable that will be executed instead of the legitimate service binary when the service starts or restarts.

Root Cause

The root cause is improper service registration during the Iskysoft Application Framework Service installation. The installer fails to enclose the service executable path in quotation marks when configuring the Windows service. This is a common oversight in Windows application development where installers register services with paths like C:\Program Files\Iskysoft\Application Framework\Service.exe instead of the properly quoted "C:\Program Files\Iskysoft\Application Framework\Service.exe".

When Windows encounters an unquoted path with spaces, it attempts to resolve the path by checking for executables at each space-delimited position. For example, it would first check C:\Program.exe, then C:\Program Files\Iskysoft\Application.exe, before eventually reaching the intended executable.

Attack Vector

The attack vector is local, requiring the attacker to have authenticated access to the vulnerable system. The attacker must identify the unquoted service path and have write permissions to one of the directories that Windows checks during path resolution. Common exploitation scenarios include:

1. Directory Hijacking: Creating a malicious executable named Program.exe in C:\ or Application.exe in C:\Program Files\Iskysoft\
2. Service Restart Trigger: Waiting for or triggering a system reboot, service crash, or manual service restart
3. Privilege Escalation: When the service starts, Windows executes the attacker's binary with SYSTEM privileges

The unquoted service path allows an attacker to place a malicious binary such as C:\Program.exe that will be executed when the ISAppService attempts to start. Since Windows services run with elevated privileges, the malicious code inherits SYSTEM-level permissions.

For detailed technical information, see the VulnCheck Advisory on iSkysoft and Exploit-DB #48171.

Detection Methods for CVE-2020-37048

Indicators of Compromise

• Presence of unexpected executables named Program.exe in the C:\ root directory
• Unusual executable files in C:\Program Files\ or C:\Program Files\Iskysoft\ directories with names like Application.exe
• Service failure events in Windows Event Log followed by successful execution of unknown processes
• New processes spawning with SYSTEM privileges from non-standard locations

Detection Strategies

• Query Windows services for unquoted paths using wmic service get name,displayname,pathname,startmode | findstr /i /v "C:\Windows\\" | findstr /i /v """ to identify vulnerable services
• Monitor file creation events in directories along the service path hierarchy (C:\, C:\Program Files\, etc.)
• Implement file integrity monitoring on directories commonly targeted by unquoted path exploits
• Deploy endpoint detection rules to alert on executable creation in root directories or program file parent directories

Monitoring Recommendations

• Enable Windows Security Event logging for process creation (Event ID 4688) with command line auditing
• Configure alerts for service start failures (Event ID 7000) followed by unexpected process execution
• Monitor for privilege escalation patterns where low-privilege users spawn SYSTEM-level processes
• Review Windows service configurations periodically using automated vulnerability scanning tools

How to Mitigate CVE-2020-37048

Immediate Actions Required

• Audit all Windows services for unquoted paths using the wmic query or PowerShell commands
• Manually correct the ISAppService registry entry by adding quotation marks around the executable path
• Restrict write permissions on the C:\ root directory and C:\Program Files\ to administrators only
• Monitor for suspicious executable creation in path resolution directories

Patch Information

No vendor patch has been identified in the available CVE data. Organizations should contact iSkysoft directly for patching guidance or consider the following remediation options:

• Check the iSkysoft Website for updated software versions
• Review the VulnCheck Advisory on iSkysoft for the latest remediation guidance
• If the software is no longer maintained, evaluate alternative solutions and plan for migration

Workarounds

• Manually fix the unquoted service path in the Windows registry by navigating to HKLM\SYSTEM\CurrentControlSet\Services\ISAppService and adding quotes around the ImagePath value
• Restrict NTFS permissions on directories in the path hierarchy to prevent unauthorized file creation
• Consider disabling the ISAppService if not required for business operations
• Implement application whitelisting to prevent execution of unauthorized binaries

# PowerShell command to identify unquoted service paths
Get-WmiObject win32_service | 
  Where-Object {$_.PathName -notmatch '^"' -and $_.PathName -match '\s'} | 
  Select-Object Name, PathName, StartMode

# Registry fix example (run as Administrator)
# Note: Backup registry before making changes
Set-ItemProperty -Path "HKLM:\SYSTEM\CurrentControlSet\Services\ISAppService" -Name "ImagePath" -Value '"C:\Program Files\Iskysoft\Application Framework\Service.exe"'