CVE-2024-38432

Executive Summary

CVE-2024-38432 is a medium-severity vulnerability (CVSS 5.5) affecting Matrix Tafnit v8, a proprietary business application framework. The vulnerability is rooted in CWE-646: Reliance on File Name or Extension of Externally-Supplied File, which allows an attacker to manipulate file processing logic by controlling the filename or extension of an uploaded or supplied file. This can lead to unauthorized file access, path traversal, or execution of unintended file operations.

The vulnerability has a low EPSS score (0.0%) and no known public exploits or proof-of-concept code at this time. However, the lack of a patch and the nature of the flaw make it a potential risk for organizations using Matrix Tafnit v8 in environments where untrusted users can supply file names.

Supply Chain & Package Security

Matrix Tafnit v8 is a proprietary software package, not distributed via public package registries (NPM, PyPI, Go, Ruby). Therefore, supply chain risks are limited to the vendor’s distribution channels. Organizations should verify the integrity of their Tafnit installation files and monitor for any vendor-issued updates or patches.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
• Base Score: 5.5 (Medium)
• Attack Vector: Local (AV:L) – The attacker must have local access to the system or be able to supply a file locally.
• Attack Complexity: Low (AC:L) – No special conditions required.
• Privileges Required: None (PR:N) – No authentication needed.
• User Interaction: Required (UI:R) – The victim must perform an action (e.g., open a file or trigger file processing).
• Scope: Unchanged (S:U) – The vulnerability does not affect other components.
• Confidentiality Impact: High (C:H) – Sensitive file contents could be exposed.
• Integrity Impact: None (I:N) – No file modification.
• Availability Impact: None (A:N) – No denial of service.

Threat Level: Medium. Exploitation requires user interaction and local access, but the potential for sensitive data exposure is significant.

Deep Dive & Mechanics

The vulnerability lies in how Matrix Tafnit v8 processes externally-supplied file names or extensions. The application relies on the file name or extension to determine how to handle the file (e.g., reading, parsing, or executing). An attacker can craft a malicious file name (e.g., ../../../etc/passwd or malicious.exe) to trick the application into:

• Path Traversal: Accessing files outside the intended directory.
• File Type Confusion: Causing the application to treat a file as a different type (e.g., treating a .txt file as an executable).
• Arbitrary File Read: Reading sensitive system files if the application uses the file name to construct file paths.

The core issue is that the application does not validate or sanitize the file name/extension before using it in file operations. This is a classic CWE-646 flaw.

Vulnerable vs. Patched Code

Since no patch is available, we can only describe the vulnerable pattern and the expected fix.

Vulnerable Code (Conceptual):

def process_file(file_name):
    # Directly uses user-supplied file name
    with open(file_name, 'r') as f:
        data = f.read()
    # Process data based on extension
    if file_name.endswith('.cfg'):
        parse_config(data)
    elif file_name.endswith('.dat'):
        parse_data(data)

Patched Code (Expected Fix):

import os

def process_file(file_name):
    # Sanitize file name: remove path traversal characters
    safe_name = os.path.basename(file_name)
    # Validate extension against whitelist
    allowed_extensions = {'.cfg', '.dat'}
    ext = os.path.splitext(safe_name)[1]
    if ext not in allowed_extensions:
        raise ValueError("Invalid file extension")
    # Use a safe base directory
    base_dir = "/app/data/uploads/"
    full_path = os.path.join(base_dir, safe_name)
    # Ensure the path is within base_dir
    if not os.path.realpath(full_path).startswith(os.path.realpath(base_dir)):
        raise ValueError("Path traversal detected")
    with open(full_path, 'r') as f:
        data = f.read()
    # Process data

Exploitation & Lab Setup

Red Team (Attack Simulation)

Prerequisites:

• Local access to a system running Matrix Tafnit v8.
• Ability to supply a file name to the application (e.g., via file upload, configuration import, or command-line argument).

Exploitation Steps:

1. Identify an input field or API endpoint that accepts a file name.
2. Craft a malicious file name to perform path traversal:
   • Example: ../../../etc/passwd
   • Example: ..\..\..\Windows\System32\config\SAM (on Windows)
3. Submit the file name to the application.
4. If the application reads the file based on the name, sensitive data will be returned.

Proof-of-Concept (Python):

import requests

url = "http://target:8080/upload"
# Attempt path traversal
files = {'file': ('../../../etc/passwd', 'dummy content')}
response = requests.post(url, files=files)
print(response.text)

Blue Team (Defense & Detection)

Detection Steps:

1. Monitor application logs for file names containing path traversal sequences (../, ..\\, %2e%2e%2f).
2. Implement file name validation at the application layer (whitelist allowed characters and extensions).
3. Use a Web Application Firewall (WAF) to block path traversal patterns.
4. Restrict application file operations to a sandboxed directory.

Lab Setup:

• Install Matrix Tafnit v8 in a controlled environment.
• Create a test user with file upload privileges.
• Use a SIEM to collect logs and trigger alerts on suspicious file names.

Indicators of Compromise (IOCs)

• File Names: Any file name containing ../, ..\\, %2e%2e, or absolute paths like /etc/passwd.
• Log Entries: Application logs showing file access attempts to paths outside the intended directory.
• Network Traffic: HTTP requests with file names containing path traversal sequences.
• System Files: Unexpected access to /etc/passwd, /etc/shadow, C:\Windows\System32\config\SAM, etc.

Detection Engineering

YARA Rule

rule CVE_2024_38432_File_Name_Traversal {
    meta:
        description = "Detects path traversal patterns in file names for CVE-2024-38432"
        author = "Valters IT"
        date = "2025-04-10"
        cve = "CVE-2024-38432"
    strings:
        $traversal1 = "../"
        $traversal2 = "..\\"
        $traversal3 = "%2e%2e%2f"
        $traversal4 = "%2e%2e\\"
        $abs_path1 = "/etc/"
        $abs_path2 = "C:\\Windows\\"
    condition:
        any of ($traversal*) or any of ($abs_path*)
}

Sigma Rule

title: CVE-2024-38432 - Path Traversal in File Name
id: 8a3f7c2e-1b4d-4e5f-9a0b-6c7d8e9f0a1b
status: experimental
description: Detects path traversal attempts in file names supplied to Matrix Tafnit v8
author: Valters IT
date: 2025-04-10
logsource:
    category: application
    product: matrix_tafnit
detection:
    selection:
        FileName|contains:
            - '../'
            - '..\\'
            - '%2e%2e%2f'
            - '%2e%2e\\'
            - '/etc/'
            - 'C:\\Windows\\'
    condition: selection
falsepositives:
    - Legitimate use of absolute paths in controlled environments
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2024-38432 - Path Traversal in File Name"; flow:to_server; content:"../"; nocase; http_client_body; sid:1000001; rev:1;)
alert http any any -> any any (msg:"CVE-2024-38432 - Path Traversal in File Name (URL encoded)"; content:"%2e%2e%2f"; nocase; http_client_body; sid:1000002; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable file upload/processing features in Matrix Tafnit v8 if not essential.
2. Implement input validation at the application layer to reject file names containing path traversal sequences.
3. Use a Web Application Firewall (WAF) to block malicious file names.

Long-Term Fix:

• Apply a vendor patch when available.
• Upgrade to a patched version of Matrix Tafnit.
• Conduct a security audit of all file handling functions.

Workarounds:

• Restrict file operations to a chroot jail or sandboxed directory.
• Use a reverse proxy to sanitize file names before they reach the application.

Valters IT
DevSecOps & Cyber Threat Intelligence Expert