CVE-2025-54832

Executive Summary

CVE-2025-54832 affects OPEXUS FOIAXpress Public Access Link (PAL) version v11.1.0. This vulnerability allows an authenticated user to add unauthorized entries to the list of states and territories. The issue stems from missing or improper authorization checks (CWE-862), enabling a low-privileged attacker to modify administrative reference data. While the CVSS score is 4.3 (Medium), the lack of a known patch and the potential for data integrity compromise in a government FOIA system elevate the risk. No public exploit code or proof-of-concept is currently available.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
• Base Score: 4.3 (Medium)
• Attack Vector: Network (AV:N)
• Attack Complexity: Low (AC:L)
• Privileges Required: Low (PR:L)
• User Interaction: None (UI:N)
• Scope: Unchanged (S:U)
• Confidentiality Impact: None (C:N)
• Integrity Impact: Low (I:L)
• Availability Impact: None (A:N)

The threat level is elevated due to the unpatched status and the sensitive nature of FOIAXpress deployments in government environments. An authenticated attacker can corrupt reference data, potentially causing misrouting of FOIA requests or administrative confusion.

Deep Dive & Mechanics

The vulnerability resides in the state/territory list management functionality of the OPEXUS FOIAXpress PAL application. The application fails to enforce proper authorization checks when an authenticated user submits a request to add a new state or territory entry. The server-side code likely trusts the client-provided user role without verifying it against a server-side session or access control list.

Attack Flow:

1. An attacker authenticates as a low-privileged user (e.g., a public requester).
2. The attacker sends a crafted HTTP POST request to the endpoint responsible for adding states/territories (e.g., /api/admin/states or similar).
3. The server processes the request without verifying that the user has administrative privileges.
4. The new entry is added to the database, corrupting the reference data.

The root cause is a missing server-side authorization check (CWE-862). The application likely relies on client-side role indicators or fails to validate the user's permissions for this specific administrative action.

Vulnerable vs. Patched Code

Since no patch is available, the following is a hypothetical comparison based on the vulnerability description.

Vulnerable Code (Conceptual):

@app.route('/api/states', methods=['POST'])
def add_state():
    # Missing authorization check
    state_name = request.json.get('name')
    state_code = request.json.get('code')
    # Directly adds to database without verifying admin role
    db.session.add(State(name=state_name, code=state_code))
    db.session.commit()
    return jsonify({"status": "success"}), 201

Patched Code (Conceptual):

@app.route('/api/states', methods=['POST'])
@admin_required  # Decorator that checks user role
def add_state():
    state_name = request.json.get('name')
    state_code = request.json.get('code')
    db.session.add(State(name=state_name, code=state_code))
    db.session.commit()
    return jsonify({"status": "success"}), 201

The patch would involve adding a server-side authorization check (e.g., a decorator or middleware) that verifies the authenticated user has an administrative role before allowing the operation.

Exploitation & Lab Setup

Red Team

Prerequisites:

• Access to an OPEXUS FOIAXpress PAL v11.1.0 instance
• Valid low-privileged user credentials (e.g., public requester account)

Exploitation Steps:

1. Authenticate to the PAL application and obtain a session token.
2. Identify the API endpoint for adding states/territories (e.g., via browser developer tools or API documentation).
3. Send a crafted POST request using curl:

curl -X POST https://target.foiaxpress.com/api/admin/states \
  -H "Authorization: Bearer <session_token>" \
  -H "Content-Type: application/json" \
  -d '{"name": "NewState", "code": "NS"}'

4. Verify the new entry appears in the state/territory list.

Expected Outcome: The new state/territory is added without administrative privileges, corrupting the reference data.

Blue Team

Detection Steps:

1. Monitor for unauthorized POST requests to state/territory management endpoints from non-admin users.
2. Review audit logs for unexpected additions to the states/territories table.
3. Implement additional logging for all administrative API calls.

Hunting Query (Splunk):

index=main sourcetype=foiaxpress_api
| search method=POST AND uri=/api/admin/states
| eval is_admin=if(role="admin", "yes", "no")
| where is_admin="no"
| table _time, user, src_ip, uri, status

Indicators of Compromise (IOCs)

• Network:
  • POST requests to /api/admin/states or similar endpoints from non-admin users
  • Unusual state/territory codes in API responses (e.g., "XX", "ZZ")
• Host:
  • Unexpected entries in the states or territories database table
  • Audit log entries showing state additions by non-admin users
• File:
  • Modified configuration files related to state/territory lists (if stored locally)

Detection Engineering

YARA Rule

rule CVE_2025_54832_FOIAXpress_State_Add {
    meta:
        description = "Detects exploitation attempts for CVE-2025-54832 - unauthorized state addition"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-54832"
    strings:
        $s1 = "/api/admin/states" ascii wide nocase
        $s2 = "addState" ascii wide nocase
        $s3 = "newState" ascii wide nocase
    condition:
        any of ($s*) and filesize < 10KB
}

Sigma Rule

title: Unauthorized State Addition in OPEXUS FOIAXpress PAL
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects attempts to add states/territories without admin privileges (CVE-2025-54832)
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
    service: access_combined
detection:
    selection:
        cs-method: 'POST'
        cs-uri-stem: '/api/admin/states'
        cs-username: '*'
    condition: selection
falsepositives:
    - Legitimate admin actions (should be rare)
level: medium
tags:
    - attack.initial_access
    - cve.2025.54832

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"CVE-2025-54832 - OPEXUS FOIAXpress PAL Unauthorized State Addition";
    flow:to_server,established;
    content:"POST";
    http_method;
    content:"/api/admin/states";
    http_uri;
    pcre:"/Authorization: Bearer [A-Za-z0-9\-_]+\r\n/H";
    sid:1000001;
    rev:1;
    reference:cve,2025-54832;
    priority:2;
)

Remediation & Mitigation

Immediate Actions:

1. Disable the state/territory management feature if not essential, by removing or restricting access to the relevant API endpoint.
2. Implement a Web Application Firewall (WAF) rule to block POST requests to /api/admin/states from non-admin IP ranges.
3. Review and audit all existing state/territory entries for unauthorized additions.

Long-term Fix:

• Apply server-side authorization checks to all administrative endpoints.
• Implement role-based access control (RBAC) with proper session validation.
• Contact OPEXUS for an official patch or upgrade to a non-vulnerable version.

Workaround:

• Restrict network access to the PAL application to trusted IP addresses only.
• Enable detailed audit logging for all API calls and monitor for anomalies.

Valters IT