CVE-2025-48394

Executive Summary

CVE-2025-48394 is a path traversal vulnerability in the Eaton CLI limited shell. An attacker with authenticated and privileged access can modify the contents of a non-sensitive file by traversing the path. The vulnerability has a CVSS score of 4.7 (Medium). The vendor has released a fix in the latest version available on the Eaton download center. No public proof-of-concept or exploit code is available at this time.

CVSS Breakdown & Threat Level

• CVSS Score: 4.7 (Medium)
• Attack Vector: Local (AV:L)
• Attack Complexity: Low (AC:L)
• Privileges Required: High (PR:H)
• User Interaction: None (UI:N)
• Scope: Unchanged (S:U)
• Confidentiality Impact: None (C:N)
• Integrity Impact: Low (I:L)
• Availability Impact: None (A:N)

The threat level is medium due to the requirement for authenticated and privileged access. The impact is limited to modifying non-sensitive files.

Deep Dive & Mechanics

The vulnerability exists in the limited shell of the Eaton CLI. The limited shell is designed to restrict user commands to a predefined set. However, due to improper input validation, an attacker with authenticated and privileged access can use path traversal sequences (e.g., ../) to escape the intended directory and modify files outside of it.

The root cause is a lack of proper sanitization of file path inputs within the CLI. The application does not check for or block path traversal characters, allowing an attacker to navigate the filesystem.

Vulnerable vs. Patched Code

Vulnerable Code (Conceptual):

def modify_file(filename, content):
    # No path traversal check
    with open(filename, 'w') as f:
        f.write(content)

Patched Code (Conceptual):

import os

def modify_file(filename, content):
    # Sanitize the filename to prevent path traversal
    safe_filename = os.path.basename(filename)
    allowed_dir = "/allowed/directory/"
    full_path = os.path.join(allowed_dir, safe_filename)
    # Ensure the final path is within the allowed directory
    if not full_path.startswith(os.path.realpath(allowed_dir)):
        raise ValueError("Invalid file path")
    with open(full_path, 'w') as f:
        f.write(content)

The patched code uses os.path.basename() to strip directory components and then verifies that the final path is within the allowed directory.

Exploitation & Lab Setup

Red Team

Prerequisites:

• Authenticated access to the Eaton device with privileged (admin) credentials.
• Access to the limited shell CLI.

Exploitation Steps:

1. Connect to the Eaton device via SSH or console.
2. Log in with privileged credentials.
3. Enter the limited shell (if not already in it).
4. Use the vulnerable command to modify a file, but with a path traversal payload.

Example Command:

modify_file ../../etc/passwd "malicious_content"

This would attempt to write "malicious_content" to /etc/passwd (or a similar system file) if the path traversal is successful.

Blue Team

Detection:

• Monitor for unusual file modification commands in the CLI logs.
• Look for path traversal patterns (e.g., ../, ..\\) in command arguments.
• Alert on attempts to modify files outside of expected directories.

Prevention:

• Apply the vendor patch immediately.
• Restrict CLI access to only trusted administrators.
• Implement additional input validation at the network level (e.g., WAF) if the CLI is exposed.

Indicators of Compromise (IOCs)

• File System Changes: Unexpected modifications to files outside of the expected application directory.
• CLI Logs: Commands containing path traversal sequences (../, ..\\).
• Network Traffic: Unusual outbound connections from the Eaton device (if the attacker exfiltrates data or downloads tools).

Detection Engineering

YARA Rule

rule CVE_2025_48394_Eaton_CLI_Path_Traversal {
    meta:
        description = "Detects path traversal attempts in Eaton CLI logs"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-48394"
    strings:
        $traversal1 = "../"
        $traversal2 = "..\\"
        $traversal3 = "%2e%2e%2f"
        $traversal4 = "%2e%2e%5c"
    condition:
        any of them
}

Sigma Rule

title: Eaton CLI Path Traversal Attempt
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects path traversal attempts in Eaton CLI logs
author: Valters IT
date: 2025/04/10
references:
    - CVE-2025-48394
logsource:
    product: eaton
    service: cli
detection:
    selection:
        Command|contains:
            - '../'
            - '..\\'
            - '%2e%2e%2f'
            - '%2e%2e%5c'
    condition: selection
falsepositives:
    - Legitimate use of path traversal in specific administrative tasks (rare)
level: high

Suricata Rule

alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"CVE-2025-48394 Eaton CLI Path Traversal Attempt"; flow:to_server,established; content:"../"; nocase; classtype:attempted-admin; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Update the Eaton device to the latest firmware version available on the Eaton download center.
2. If patching is not immediately possible, restrict CLI access to only trusted administrators via network segmentation and access control lists.

Long-Term Measures:

• Implement strict input validation for all CLI commands.
• Use a chroot jail or similar mechanism to restrict the limited shell to a specific directory.
• Regularly audit CLI logs for suspicious activity.

Valters IT Signature

This report was generated by Valters IT Cyber Threat Intelligence. For questions, contact intelligence@valters-it.com.