CVE-2024-13186

Executive Summary

CVE-2024-13186 is a security advisory affecting the MinigameCenter module, which is likely a component of a larger web application or content management system. The vulnerability stems from insufficient restrictions on loading URLs, potentially allowing an attacker to perform Server-Side Request Forgery (SSRF) attacks. This could lead to information leakage, such as internal network details, cloud metadata, or sensitive configuration files. The CVSS score is 0.0, indicating that no official CVSS vector has been assigned, but based on the description, the impact is likely limited to information disclosure. No public proof-of-concept (PoC) or exploit code is available at this time.

Supply Chain & Package Security

The MinigameCenter module is not a standard package in NPM, PyPI, Go, or Ruby registries. It is likely a custom or proprietary module. Therefore, supply chain security risks are limited to the module's distribution method. Users should verify the integrity of the module source and ensure it is obtained from a trusted repository.

CVSS Breakdown & Threat Level

While no official CVSS vector is provided, a reasonable assessment based on the description is:

• Attack Vector (AV): Network (N) – The vulnerability can be exploited remotely.
• Attack Complexity (AC): Low (L) – No special conditions are required.
• Privileges Required (PR): None (N) – No authentication needed.
• User Interaction (UI): None (N) – No user action required.
• Scope (S): Unchanged (U) – The vulnerable component and the affected resource are in the same security authority.
• Confidentiality (C): Low (L) – Limited information disclosure.
• Integrity (I): None (N) – No data modification.
• Availability (A): None (N) – No impact on availability.

Threat Level: Medium (estimated CVSS 5.3). The lack of public exploits and the limited impact (information leakage) reduce the immediate threat, but SSRF vulnerabilities can be chained with other attacks.

Deep Dive & Mechanics

The MinigameCenter module likely provides functionality to fetch or load external URLs, such as game assets, APIs, or user-provided links. The vulnerability arises when the module does not properly validate or restrict the URLs it loads. An attacker can craft a request that forces the server to make a request to an internal resource, such as:

• http://localhost/ – Access local services.
• http://169.254.169.254/ – Cloud metadata (AWS, GCP, Azure).
• file:///etc/passwd – Local file inclusion (if supported).
• http://internal-server/ – Internal network scanning.

The lack of a URL whitelist or blacklist, combined with insufficient input validation, allows the attacker to control the target of the server-side request. This can lead to information leakage, such as reading internal files or accessing cloud instance metadata.

Vulnerable vs. Patched Code

Since no patch is available, the vulnerable code likely resembles:

// Vulnerable code
function fetchUrl(url) {
    // No validation of URL
    return http.get(url);
}

A patched version would include URL validation:

// Patched code
const allowedDomains = ['games.example.com', 'cdn.example.com'];
function fetchUrl(url) {
    const parsedUrl = new URL(url);
    if (!allowedDomains.includes(parsedUrl.hostname)) {
        throw new Error('URL not allowed');
    }
    return http.get(url);
}

Exploitation & Lab Setup

Red Team

Lab Setup:

1. Deploy a vulnerable instance of MinigameCenter (e.g., using a Docker container with the module).
2. Set up a listener (e.g., nc -lvnp 4444) to capture outbound requests.
3. Use Burp Suite or curl to send malicious requests.

Exploitation Steps:

1. Identify the vulnerable endpoint (e.g., /fetch?url=).
2. Test with a simple external URL to confirm functionality: http://attacker.com/test.
3. Attempt SSRF to internal resources:
   • http://127.0.0.1:8080/admin
   • http://169.254.169.254/latest/meta-data/
4. Use a redirect or DNS rebinding to bypass weak filters.

Example Request:

GET /fetch?url=http://169.254.169.254/latest/meta-data/ HTTP/1.1
Host: target.com

Blue Team

Detection:

• Monitor outbound connections to unusual IPs (e.g., 169.254.169.254, internal ranges).
• Alert on requests to localhost or private IPs from the web server.
• Use the Sigma rule below to detect SSRF attempts.

Mitigation:

• Implement a strict URL whitelist.
• Disable unnecessary URL schemes (e.g., file://, gopher://).
• Use a network firewall to block outbound traffic to internal IPs from the web tier.

Indicators of Compromise (IOCs)

• Network:
  • Outbound HTTP requests to 169.254.169.254 (cloud metadata).
  • Requests to 127.0.0.1, localhost, or 0.0.0.0.
  • Requests to internal IP ranges (e.g., 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16).
• Logs:
  • Web server logs showing GET /fetch?url=http://... with internal IPs.
  • Error logs indicating failed URL parsing or connection attempts.

Detection Engineering

YARA Rule

rule CVE_2024_13186_SSRF_Attempt {
    meta:
        description = "Detects SSRF attempts targeting internal IPs or cloud metadata"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2024-13186"
    strings:
        $ip1 = "169.254.169.254"
        $ip2 = "127.0.0.1"
        $ip3 = "localhost"
        $ip4 = "0.0.0.0"
        $internal = /10\.\d{1,3}\.\d{1,3}\.\d{1,3}|172\.(1[6-9]|2\d|3[01])\.\d{1,3}\.\d{1,3}|192\.168\.\d{1,3}\.\d{1,3}/
    condition:
        any of ($ip*) or $internal
}

Sigma Rule

title: SSRF Attempt via MinigameCenter Module
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects HTTP requests to internal IPs or cloud metadata from MinigameCenter
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-uri-query|contains:
            - 'url=http://169.254.169.254'
            - 'url=http://127.0.0.1'
            - 'url=http://localhost'
            - 'url=http://10.'
            - 'url=http://172.'
            - 'url=http://192.168.'
    condition: selection
falsepositives:
    - Legitimate internal API calls (if allowed)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2024-13186 SSRF Attempt - Internal IP"; flow:to_server; content:"GET"; http_method; content:"/fetch?url="; http_uri; content:"169.254.169.254"; within:50; sid:1000001; rev:1;)
alert http any any -> any any (msg:"CVE-2024-13186 SSRF Attempt - Localhost"; flow:to_server; content:"GET"; http_method; content:"/fetch?url="; http_uri; content:"127.0.0.1"; within:50; sid:1000002; rev:1;)

Remediation & Mitigation

1. Immediate Actions:

   • Disable the vulnerable endpoint if not required.
   • Implement a URL whitelist allowing only trusted domains.
   • Apply input validation to reject URLs containing internal IPs or special schemes.

2. Long-term Fix:

   • Update to a patched version of the MinigameCenter module (once available).
   • Conduct a code review to ensure all URL loading functions are secure.

3. Network Controls:

   • Use egress filtering to block outbound traffic to private IPs from the web server.
   • Deploy a Web Application Firewall (WAF) with rules to detect SSRF patterns.

4. Monitoring:

   • Enable logging for all URL fetch requests.
   • Set up alerts for anomalous outbound connections.

Valters IT signature: This report is generated by an AI assistant specialized in DevSecOps and Cyber Threat Intelligence. For questions, contact Valters IT.