CVE-2026-26033: UPS Multi-UPS MUMC RCE Vulnerability

CVE-2026-26033 Overview

CVE-2026-26033 is an Unquoted Search Path or Element vulnerability (CWE-428) affecting the UPS Multi-UPS Management Console (MUMC) version 01.06.0001 (A03). This vulnerability allows a local attacker with write access to a directory on the system drive to execute arbitrary code with SYSTEM privileges, representing a significant privilege escalation risk in enterprise environments.

Critical Impact

Local privilege escalation to SYSTEM-level access through unquoted service path exploitation, enabling complete system compromise.

Affected Products

• UPS Multi-UPS Management Console (MUMC) version 01.06.0001 (A03)

Discovery Timeline

• 2026-03-05 - CVE-2026-26033 published to NVD
• 2026-03-05 - Last updated in NVD database

Technical Details for CVE-2026-26033

Vulnerability Analysis

The vulnerability exists due to improper handling of service executable paths in the UPS Multi-UPS Management Console software. When Windows services are configured with executable paths containing spaces and these paths are not enclosed in quotation marks, the Windows Service Control Manager (SCM) interprets the path ambiguously. This creates an opportunity for attackers to place malicious executables in strategic locations along the unquoted path.

When the vulnerable service starts or restarts, Windows will attempt to locate and execute the binary by parsing the unquoted path from left to right, testing each space-delimited segment as a potential executable. An attacker who places a malicious executable at one of these intermediate path locations can hijack the service execution flow.

The local attack vector requires the attacker to have write access to a directory on the system drive. Once exploited, the attacker gains code execution with SYSTEM privileges—the highest privilege level on Windows systems—enabling full control over the affected machine.

Root Cause

The root cause is the failure to properly quote the service executable path in the Windows service configuration. Service paths containing spaces must be enclosed in double quotation marks to prevent Windows from misinterpreting the path segments. The MUMC installer or service registration process failed to apply this security best practice, leaving the service path vulnerable to hijacking.

Attack Vector

The attack requires local access to the system with write permissions to a directory along the unquoted service path. The attacker must:

1. Identify the unquoted service path used by the MUMC service
2. Determine which intermediate path locations are writable
3. Place a malicious executable with an appropriate name at one of these locations
4. Wait for or trigger a service restart to execute the malicious payload with SYSTEM privileges

The vulnerability manifests when Windows parses the unquoted service path during service startup. For example, if a service path is C:\Program Files\UPS Management\Service.exe, Windows will sequentially try to execute C:\Program.exe, then C:\Program Files\UPS.exe, and so on until it finds a valid executable. An attacker placing a malicious Program.exe in C:\ or UPS.exe in C:\Program Files\ can intercept execution.

For detailed technical information, see the JVN Security Alert #JVN56544509 and the Dell Driver Update Advisory.

Detection Methods for CVE-2026-26033

Indicators of Compromise

• Unexpected executable files appearing in root directories (e.g., C:\Program.exe) or intermediate path directories
• Service execution from unexpected file locations rather than the legitimate installation directory
• Unusual process trees showing SYSTEM-level processes spawning from non-standard paths
• File system audit logs showing write operations to privileged directories by non-administrative users

Detection Strategies

• Use Windows Event Logs to monitor Service Control Manager events (Event ID 7045 for new service installations, Event ID 7036 for service state changes)
• Deploy file integrity monitoring solutions to detect new or modified executables in system directories and common unquoted path locations
• Run periodic audits using tools like wmic service get name,displayname,pathname,startmode to identify services with unquoted paths containing spaces
• Monitor process creation events for SYSTEM-level processes executing from unusual directory locations

Monitoring Recommendations

• Enable Windows Security Audit policies for process creation and file system access
• Configure SIEM rules to alert on executable files created in C:\ root or C:\Program Files\ with names that could exploit unquoted paths
• Implement application whitelisting to prevent unauthorized executables from running in system directories
• Regularly scan for unquoted service paths across managed systems using vulnerability assessment tools

How to Mitigate CVE-2026-26033

Immediate Actions Required

• Update the UPS Multi-UPS Management Console to the latest patched version available from the vendor
• Audit the affected system for any suspicious executables in directories along the service path
• Restrict write permissions on system directories to administrative accounts only
• Review and remediate any other services on the system with unquoted paths containing spaces

Patch Information

Dell has released an update to address this vulnerability. System administrators should download and apply the latest driver and software update from the Dell Driver Update Advisory. Additional details are available in the JVN Security Alert #JVN56544509.

Workarounds

• Manually correct the service path by adding quotation marks around the executable path in the Windows Registry under HKLM\SYSTEM\CurrentControlSet\Services\<ServiceName>\ImagePath
• Remove write permissions for non-administrative users from directories that could be exploited (e.g., C:\, C:\Program Files\)
• Disable the vulnerable service temporarily if it is not critical to operations until the patch can be applied
• Implement application control policies to prevent execution of unauthorized binaries in system directories

# Check for unquoted service paths on Windows (PowerShell)
Get-WmiObject -Class Win32_Service | Where-Object { $_.PathName -notlike '"*' -and $_.PathName -like '* *' } | Select-Object Name, PathName