CVE-2025-55076: Unveiling a Root Privilege Escalation in Plugin Alliance Installation Manager

Overview

CVE-2025-55076 is a local privilege escalation vulnerability affecting the InstallationHelper service included with Plugin Alliance Installation Manager v1.4.0 for macOS. This flaw allows a malicious local user to potentially gain root privileges on the affected system. The vulnerability stems from the service’s acceptance of unauthenticated XPC connections and the subsequent execution of user-supplied input via the system() call.

Technical Details

The Plugin Alliance Installation Manager utilizes the InstallationHelper service to perform tasks requiring elevated privileges. However, version 1.4.0 of this service is vulnerable due to the following:

• Unauthenticated XPC Connections: The InstallationHelper service accepts XPC (Inter-Process Communication) connections without proper authentication. This means any local user can establish a connection with the service.
• Unsafe system() Usage: The service processes input received through XPC connections and directly passes it to the system() function. The system() function executes a shell command, making the application highly susceptible to command injection attacks if the input is not carefully sanitized.

An attacker can exploit this by crafting a malicious XPC request containing arbitrary commands. When the InstallationHelper service processes this request, it will execute the attacker’s commands with root privileges, effectively allowing them to take complete control of the system.

Example exploit scenario:

          
          # Example of a hypothetical exploit (Proof-of-Concept)
          # Warning: Running this code on your system might cause damage. Use with caution.
          # This is a simplified representation and requires macOS specific XPC handling.

          import os
          import subprocess

          # Craft the malicious command
          malicious_command = "open /Applications/Calculator.app"  # Replace with a more harmful command if needed

          # Simulate sending this command via XPC to InstallationHelper
          # In a real exploit, you would use macOS's XPC API to send this data
          try:
            subprocess.run(['/bin/sh', '-c', malicious_command], check=True, capture_output=True, text=True, user="root") #THIS SIMULATES THE PROBLEM - real exploitation involves sending via XPC

          except subprocess.CalledProcessError as e:
            print(f"Error: {e}")
            print(f"Stdout: {e.stdout}")
            print(f"Stderr: {e.stderr}")

          print("Command (simulated to have been) executed with root privileges.")
          
        

CVSS Analysis

The vulnerability has a CVSS v3 score of 6.2 (MEDIUM).

• CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
• Attack Vector (AV): Local (L) – The attacker must have local access to the system.
• Attack Complexity (AC): Low (L) – The vulnerability is relatively easy to exploit.
• Privileges Required (PR): None (N) – No privileges are required to exploit the vulnerability.
• User Interaction (UI): None (N) – No user interaction is required to exploit the vulnerability.
• Scope (S): Unchanged (U) – An exploited vulnerability can only affect resources managed by the same security authority.
• Confidentiality Impact (C): High (H) – There is a total loss of confidentiality, resulting in all system information being divulged.
• Integrity Impact (I): High (H) – There is a total loss of integrity; the attacker can modify any files or settings on the system.
• Availability Impact (A): None (N) – There is no impact to system availability. While the attacker could cause issues, the CVSS score reflects that the primary attack vector leads to privilege escalation with impact on confidentiality and integrity.

Possible Impact

Successful exploitation of CVE-2025-55076 can have severe consequences:

• Full System Compromise: An attacker can gain root privileges, allowing them to install malware, steal sensitive data, modify system configurations, and create persistent backdoors.
• Data Breach: Access to sensitive user data and system configuration files could lead to a significant data breach.
• Denial of Service (DoS): While the CVSS Availability impact is None, an attacker with root access could intentionally cause a denial of service by modifying or deleting critical system files.

Mitigation and Patch Steps

The primary mitigation is to upgrade to a patched version of Plugin Alliance Installation Manager that addresses this vulnerability. Contact Plugin Alliance support to inquire about the availability of a patch. In the interim, consider these temporary mitigations:

• Disable or Restrict the InstallationHelper Service: If feasible, disable the InstallationHelper service. However, this might impact the functionality of the Plugin Alliance Installation Manager.
• Monitor XPC Connections: Implement monitoring to detect suspicious XPC connections to the InstallationHelper service. This requires advanced macOS system monitoring capabilities.

Recommended Action: Immediately upgrade to the latest version of Plugin Alliance Installation Manager as soon as a patched version is released.

References

• Almighty Security Advisory on Plugin Alliance HelperTool XPC Service Local Privilege Escalation