CVE-2024-49501

Executive Summary

CVE-2024-49501 is an incorrect authorization vulnerability in OMRON Sysmac Studio, an industrial automation programming environment. The flaw allows an attacker with local access to bypass the Data Protection function, potentially exposing proprietary control logic and intellectual property. With a CVSS score of 5.7 (Medium), the risk is elevated in environments where untrusted personnel have physical or remote desktop access to engineering workstations. No public exploit code or patch is currently available, but the vulnerability is confirmed by the vendor.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
• Base Score: 5.7 (Medium)
• Attack Vector: Local (requires physical or remote desktop access)
• Attack Complexity: Low
• Privileges Required: Low (user-level access)
• User Interaction: None
• Scope: Unchanged
• Confidentiality Impact: High (protected program data exposed)
• Integrity Impact: None
• Availability Impact: None

The threat is primarily to confidentiality of proprietary control logic. Exploitation does not require special privileges beyond standard user access to the workstation.

Deep Dive & Mechanics

The vulnerability resides in the authorization mechanism of Sysmac Studio’s Data Protection function. This feature is designed to encrypt or restrict access to project files containing PLC (Programmable Logic Controller) code. Due to an incorrect authorization check, a local user can bypass the protection and read the program data without proper credentials.

Root Cause: The application fails to validate the user’s authorization level before granting read access to protected project files. This is a classic CWE-863 (Incorrect Authorization) issue.

Attack Scenario: An attacker with local access to a workstation running Sysmac Studio can navigate to the project directory and open protected files directly, bypassing the intended password prompt. The attacker does not need to know the Data Protection password.

Impact: Exposure of proprietary control algorithms, production logic, and potentially sensitive industrial process parameters. This could enable further attacks on the ICS/SCADA environment.

Vulnerable vs. Patched Code

No official patch is available. The vulnerable code is in the authorization module of Sysmac Studio. A hypothetical fix would involve adding a proper authorization check before allowing access to protected project files.

Vulnerable (pseudocode):

if (user.HasAccessToFile(filePath))
{
    // Incorrect: only checks file system permissions, not Data Protection
    LoadProject(filePath);
}

Patched (pseudocode):

if (user.HasAccessToFile(filePath) && user.IsAuthorizedForDataProtection(filePath))
{
    LoadProject(filePath);
}
else
{
    ShowPasswordPrompt();
}

Exploitation & Lab Setup

Red Team

Prerequisites:

• OMRON Sysmac Studio installed on a Windows workstation.
• A project file protected with the Data Protection function.
• Local user-level access to the workstation.

Steps:

1. Identify the Sysmac Studio project directory (typically C:\Users\<user>\Documents\OMRON\Sysmac Studio\Projects).
2. Locate a .smc2 or .smc project file that has Data Protection enabled.
3. Open the file directly using a text editor or by importing it into a new Sysmac Studio instance without providing the password.
4. The project contents (ladder logic, structured text, etc.) will be accessible.

Proof of Concept:

# PowerShell script to copy protected project file
Copy-Item "C:\Users\victim\Documents\OMRON\Sysmac Studio\Projects\secret_project.smc2" "C:\temp\"
# Open in Sysmac Studio without password
Start-Process "C:\Program Files\OMRON\Sysmac Studio\SysmacStudio.exe" -ArgumentList "C:\temp\secret_project.smc2"

Blue Team

Detection:

• Monitor for unauthorized access to Sysmac Studio project directories.
• Alert on processes reading .smc2 or .smc files without the Sysmac Studio UI being in focus.
• Use file integrity monitoring (FIM) on project directories.

Hunting:

• Search for event logs showing SysmacStudio.exe accessing protected files.
• Look for copies of project files in non-standard locations (e.g., C:\temp, %TEMP%).

Indicators of Compromise (IOCs)

• File Access: Unauthorized reads of .smc2 or .smc files in C:\Users\*\Documents\OMRON\Sysmac Studio\Projects\
• Process Anomaly: SysmacStudio.exe launched with command-line arguments pointing to a project file outside the standard directory.
• Network: No network-based IOCs; exploitation is local.
• Registry: No known registry changes.

Detection Engineering

YARA Rule

rule CVE_2024_49501_OMRON_DataProtection_Bypass {
    meta:
        description = "Detects attempts to access OMRON Sysmac Studio protected project files"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2024-49501"
    strings:
        $smc2 = ".smc2" nocase
        $smc = ".smc" nocase
        $sysmac = "Sysmac Studio" nocase
    condition:
        ($smc2 or $smc) and $sysmac
}

Sigma Rule

title: OMRON Sysmac Studio Data Protection Bypass
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects unauthorized access to OMRON Sysmac Studio protected project files
author: Valters IT
date: 2025/04/10
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2024-49501
logsource:
    category: file_event
    product: windows
detection:
    selection:
        TargetFilename|contains:
            - '.smc2'
            - '.smc'
        Image|endswith: '\SysmacStudio.exe'
    condition: selection
falsepositives:
    - Legitimate use by authorized engineers
level: medium

Suricata Rule

alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"CVE-2024-49501 OMRON Sysmac Studio Data Protection Bypass - Potential Exfiltration"; flow:to_server,established; content:"|2e 73 6d 63 32|"; nocase; content:"Sysmac Studio"; nocase; classtype:attempted-user; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Restrict physical and remote desktop access to engineering workstations running Sysmac Studio.
2. Use Windows file permissions to limit read access to project directories to only authorized users.
3. Enable Windows auditing on project file access.

Long-Term Fix:

• Apply vendor patch when released.
• Implement application whitelisting to prevent unauthorized execution of Sysmac Studio.
• Use full-disk encryption (e.g., BitLocker) to protect data at rest.

Workaround:

• Store protected project files on encrypted volumes with separate access controls.
• Do not rely solely on Sysmac Studio’s Data Protection function for sensitive projects.

Valters IT
Securing Industrial Environments, One CVE at a Time.