CVE-2024-8586

Executive Summary

CVE-2024-8586 is an Open Redirect vulnerability identified in the WebITR application by Uniong. This flaw allows an unauthenticated, remote attacker to craft a malicious URL that, when clicked by a legitimate user, redirects them to an external, attacker-controlled domain. The attack exploits the trust users place in the WebITR domain, making it a potent vector for phishing campaigns. The vulnerability has a CVSS v3.1 base score of 6.1 (Medium), with the primary impact being on user confidentiality and integrity through social engineering. No public proof-of-concept (PoC) code or patch is currently available, and the EPSS score is 0.0%, indicating low exploitation activity in the wild at the time of analysis.

Supply Chain & Package Security

This vulnerability is not related to an open-source package manager (NPM, PyPI, Go, Ruby). It affects a proprietary web application (WebITR) from Uniong. Therefore, supply chain security considerations are limited to ensuring the integrity of the vendor's software distribution and update channels.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
• Base Score: 6.1 (Medium)
• Attack Vector (AV): Network (N) – The vulnerability is exploitable remotely.
• Attack Complexity (AC): Low (L) – No special conditions are required for exploitation.
• Privileges Required (PR): None (N) – No authentication is needed to trigger the redirect.
• User Interaction (UI): Required (R) – The victim must click the crafted URL.
• Scope (S): Changed (C) – The redirect can lead to a resource outside the WebITR application's security scope.
• Confidentiality Impact (C): Low (L) – Limited information disclosure via phishing.
• Integrity Impact (I): Low (L) – The attacker can manipulate the user's view of a trusted site.
• Availability Impact (A): None (N) – No impact on system availability.

Threat Level: Medium. While the technical impact is low, the social engineering potential is high, making it a useful tool for targeted phishing attacks.

Deep Dive & Mechanics

The Open Redirect vulnerability in WebITR likely resides in a URL parameter that accepts a redirect destination without proper validation. For example, a parameter such as ?redirect= or ?url= may be used to return users to a previous page after login or form submission. If the application does not validate that the destination is within the same domain, an attacker can supply an external URL.

Example vulnerable request:

https://webitr.example.com/login?redirect=https://evil.com/phishing

When a user clicks this link, they are taken to the legitimate WebITR login page. After authentication (or immediately, depending on the implementation), the application redirects the browser to https://evil.com/phishing, which can be a clone of the login page to steal credentials.

The attack flow:

1. Attacker crafts a URL: https://webitr.example.com/some-endpoint?next=https://attacker.com
2. Attacker distributes the URL via email, social media, or other channels.
3. Victim clicks the link, sees the legitimate WebITR domain in the address bar initially.
4. The application processes the next parameter and issues a 302 redirect to https://attacker.com.
5. Victim is now on the attacker's site, potentially entering sensitive information.

Vulnerable vs. Patched Code

Since no patch is available, the vulnerable code pattern is inferred. A typical vulnerable implementation in a web application might look like this:

Vulnerable (PHP example):

<?php
$redirect = $_GET['redirect'];
header("Location: " . $redirect);
exit;
?>

Patched (Secure) Code:

<?php
$redirect = $_GET['redirect'];
$allowed_hosts = ['webitr.example.com', 'www.example.com'];
$parsed_url = parse_url($redirect);
if (in_array($parsed_url['host'], $allowed_hosts)) {
    header("Location: " . $redirect);
    exit;
} else {
    // Redirect to a default safe page
    header("Location: /dashboard");
    exit;
}
?>

The patched version validates the redirect URL against a whitelist of allowed hosts. Without a vendor patch, administrators must implement such validation at the web server level (e.g., using a reverse proxy or WAF rule).

Exploitation & Lab Setup

Red Team (Offensive)

Lab Setup:

1. Target: A test instance of WebITR (if available) or a simulated vulnerable application.
2. Attacker Machine: Kali Linux or any system with a web browser and netcat.
3. Phishing Server: A simple HTTP server to capture credentials (e.g., Python's http.server or a tool like evilginx2).

Exploitation Steps:

1. Identify the vulnerable parameter by fuzzing common redirect parameters (redirect, url, next, return, goto, target).
2. Craft a malicious URL:

   https://webitr.example.com/login?redirect=http://attacker.com/steal.php
   

3. Send the URL to the victim via email or social engineering.
4. Set up a listener on the attacker server to capture incoming requests:

   nc -lvnp 80
   

5. When the victim clicks the link, they will be redirected to the attacker's server. If the attacker hosts a phishing page, they can capture credentials.

Automated Scanning with Nuclei (if template existed):

id: CVE-2024-8586
info:
  name: WebITR Open Redirect
  severity: medium
  description: WebITR from Uniong has an Open Redirect vulnerability.
  reference: https://nvd.nist.gov/vuln/detail/CVE-2024-8586
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
    cvss-score: 6.1
    cwe-id: CWE-601
requests:
  - method: GET
    path:
      - "{{BaseURL}}/login?redirect=http://evil.com"
    matchers:
      - type: regex
        part: header
        regex:
          - "(?i)Location: http://evil\\.com"

Blue Team (Defensive)

Detection & Prevention:

1. Web Application Firewall (WAF) Rule: Block requests with redirect parameters pointing to external domains.

   if ($arg_redirect ~* "^https?://(?!webitr\.example\.com)") {
       return 403;
   }
   

2. Log Monitoring: Monitor web server logs for unusual redirect patterns.

   grep -E "redirect=|url=|next=" /var/log/nginx/access.log | grep -v "webitr.example.com"
   

3. User Awareness: Train users to verify URLs before clicking, even if they appear to be from a trusted domain.

Indicators of Compromise (IOCs)

• URL Patterns:
  • https://webitr.example.com/*?redirect=http://*
  • https://webitr.example.com/*?url=https://*
  • https://webitr.example.com/*?next=*
• HTTP Response Headers:
  • Location: http://evil.com (or any external domain)
• Network Traffic:
  • Outbound connections to known phishing domains shortly after a request to WebITR.
• Log Entries:
  • GET /login?redirect=http://evil.com with a 302 response code.

Detection Engineering

YARA Rule

rule CVE_2024_8586_WebITR_Open_Redirect {
    meta:
        description = "Detects potential open redirect exploitation attempts against WebITR"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2024-8586"
    strings:
        $redirect_param = /[?&](redirect|url|next|return|goto|target)=http/i
        $webitr_path = /\/login|\/logout|\/index\.php/i
    condition:
        $redirect_param and $webitr_path
}

Sigma Rule

title: WebITR Open Redirect Exploitation Attempt
id: 8a9b3c2d-1e5f-4a7b-9c8d-0e1f2a3b4c5d
status: experimental
description: Detects HTTP requests to WebITR with suspicious redirect parameters pointing to external domains.
author: Valters IT
date: 2025/04/10
logsource:
    category: webserver
    product: nginx
detection:
    selection:
        cs-method: 'GET'
        cs-uri-query|contains:
            - 'redirect=http'
            - 'url=http'
            - 'next=http'
        cs-host: 'webitr.example.com'
    condition: selection
falsepositives:
    - Legitimate redirects to partner sites (if any)
level: medium

Suricata Rule

alert http any any -> any any (msg:"CVE-2024-8586 WebITR Open Redirect Attempt"; flow:to_server,established; content:"GET"; http_method; content:"/login"; http_uri; content:"redirect=http"; http_uri; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Vendor Patch: Contact Uniong for an official patch. Since none is available, implement a virtual patch.
2. Web Server Configuration: Add a rewrite rule to validate redirect parameters.

   RewriteEngine On
   RewriteCond %{QUERY_STRING} (redirect|url|next)=http:// [NC]
   RewriteRule ^ - [F,L]
   

3. Input Validation: If source code access is available, implement a whitelist of allowed redirect destinations.

Long-Term Fix:

• The vendor must release a security update that validates redirect URLs against a whitelist of internal domains.
• Implement Content Security Policy (CSP) headers to restrict form actions and navigation.

Workaround:

• Disable the redirect functionality entirely if not critical to business operations.
• Use a reverse proxy to intercept and validate all redirect parameters.

Valters IT