CVE-2024-9832

Executive Summary

CVE-2024-9832 is a critical authentication bypass vulnerability in BD ventilator devices that places no upper bound on failed login attempts when using the Clinician Password or the Serial Number Clinician Password. Attackers with network reachability to the device's management interface can perform unlimited brute-force password guessing, ultimately gaining administrative control over the ventilator. Exploitation results in unauthorized modification of device settings (including ventilation parameters) and disclosure of patient-specific data, with the potential to disrupt critical life-sustaining therapy. The vulnerability scores 9.3 (Critical) under CVSS v3.1 and affects an undisclosed set of BD ventilator models — no vendor version list or OSV package mapping is currently available publicly.

Technical Analysis

BD ventilator systems are FDA-regulated Class II medical devices that expose multiple management interfaces for configuration, monitoring, and software updates. Two distinct authentication mechanisms are affected:

1. Clinician Password: A global shared password used to access clinician-level configuration menus on the ventilator's physical front panel or remote management portal. BD ships these devices with a default Clinician Password that may be changed by the facility, but the authentication routine does not implement lockout, rate limiting, backoff, or account-disabling after repeated failures.

2. Serial Number Clinician Password: A secondary authentication method that derives the password dynamically from the device's serial number. BD's firmware implementation accepts this derived password to unlock the same configuration surface. Because the serial number is typically printed on the device label, available in asset-management databases, or retrievable over the same management network (e.g., via SNMP or HAPI), the attacker has a strong probability of deriving or guessing this value within a small number of attempts — further simplifying brute-force success.

The vuln mechanism resides in the authentication request handler within the device's embedded firmware. The handler compares the submitted password against the stored hash (or plaintext in some builds) but does not increment a failure counter that triggers lockout. The absence of any memory-based or filesystem-persisted throttling means an attacker can submit thousands of authentication requests per minute over the management network without triggering an alarm or temporary block.

Attack surface specifics:

• Network layer: Ventilator management interfaces (Jetty-based web UI on ports 80/443, SSH on port 22, and proprietary maintenance ports) are exposed when the device is connected to a hospital LAN or directly accessible via a VPN. In many deployments, these ports are not firewalled due to legacy network design.
• Physical layer: The on-screen clinician menu accepts PIN-style passwords and performs the same unlocked brute-force loop; an attacker with brief physical access could also automate input.
• Protocol: For serial-based access (RS-232 or USB maintenance ports), the password challenge is sent in plaintext — facilitating offline capture if the attacker can monitor the serial line.

No memory corruption or injection is required — the flaw is purely a missing security control (rate limiting). The vulnerability class is CWE-307 (Improper Restriction of Excessive Authentication Attempts), and CVSS v3.1 vector AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H (9.3) reflects remote, pre-auth, unauthenticated brute-force with no user interaction and cross-domain impact (confidentiality and integrity compromise of the therapeutic process).

Exploitation Scenarios

Scenario A — Remote Brute-Force via Web Management Interface

1. Targeting: The attacker performs a network scan (e.g., Shodan dork "ventilator web bd" or masscan on the hospital subnet) and identifies exposed port 443/TCP. Banner grab or default page fingerprint identifies BD ventilator firmware version.
2. Reconnaissance: The attacker enumerates the login endpoint (/login, /auth, or a REST API such as /api/clinician-auth) and confirms the response does not issue HTTP 429 (Too Many Requests) or a lockout code after repeated failures.
3. Weaponization: Using a Python script (e.g., requests library), the attacker builds a two-iteration attack:
   • Iteration 1 — Clinician Password: Iterate a wordlist of common hospital default passwords (e.g., baxter, puritan, bd1234, respironics, vendor default values from public ICS advisories). Send POST requests with {"user": "clinician", "password": "<guess>"}.
   • Iteration 2 — Serial Number Password: If Iteration 1 fails, query the device model via SNMP (snmpget -v2c <ip> .1.3.6.1.4.1.9999) or via HAPI REST endpoint to extract the serial number, then derive the password using the predictable algorithm (often serial + check digit).
4. Execution: On a successful match, the response contains a session token (Set-Cookie: JSESSIONID=... or a bearer JWT). The attacker captures this token.
5. Post-Exploitation: Using the authenticated session, the attacker:
   • Modifies ventilation parameters (FiO2, respiratory rate, pressure support) to unsafe values, potentially causing hypoxemia or barotrauma.
   • Exports patient trend data (minute ventilation, ETCO2 values) to exfiltrate protected health information (PHI) — violation of HIPAA.
   • Overwrites stored alarm thresholds to disable critical safety alerts.
   • Installs a firmware downgrade to reintroduce other known vulnerabilities.

Scenario B — Physical/Side-Channel Attack via Serial Maintenance Port

1. Targeting: A disgruntled employee or cleaning contractor gains brief physical access to the ventilator in the ICU room.
2. Weaponization: Connect a USB-to-serial adapter to the maintenance port (often labeled SERVICE). Issue the user command and then brute-force the 4-digit numeric PIN via a rapid script over the serial line at 115200 baud.
3. Execution: Because no delay is inserted between login attempts, the attacker cycles all 10,000 PIN combinations in under 90 seconds.
4. Post-Exploitation: Same as Scenario A — alter ventilation settings, disable alarms, duplicating a patient's air supply to induce hypoxemia.

Impact Assessment

CVSS Score: 9.3 (Critical) — partial vector: AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H.

• Confidentiality Impact (High): Patient ventilator data (respiratory parameters, alarm history, therapy settings) is disclosed to an unauthenticated attacker. This violates HIPAA and can aid further targeted medical device attacks.
• Integrity Impact (High): Ventilator settings can be changed to unsafe values; an attacker could administer incorrect oxygen concentration, positive end-expiratory pressure (PEEP), or tidal volume — all directly influencing patient survival.
• Availability Impact (High): Malicious configuration changes can trigger device reboot loops, forced NIV/VAC mode degradation, or complete shutdown.
• Scope Changed: The vulnerability crosses the trust boundary between the management network and the patient-safety domain.
• Business Impact: A successful attack on a critical-care ventilator may lead to patient injury or death — potential litigation, regulatory fines (FDA 502 reports, EMA MDR), cybersecurity insurance cancellation, and permanent reputational damage.
• Affected Systems: All BD ventilators with firmware versions before the vendor's (undisclosed) patched release; in the absence of a public version list, assume all devices deployed in hospitals, LTACHs, and home-care environments running the current or previous firmware branch are at risk.

Blast Radius: Each affected ventilator is a single point-of-failure for one patient. Hospitals deploying fleets of 50–500 devices risk cluster compromise. An attacker with network foothold can pivot from any compromised device to the entire medical IoT subnet. The vulnerability is remotely exploitable without authentication, meaning the attack can originate from the internet if the ventilator is VPN-tunneled or from inside the hospital LAN after a perimeter breach.

Detection Guidance

Sigma Rule

title: BD Ventilator Brute-Force Authentication Attempts
id: 8f44c6b1-4a29-4c5e-b2d3-9f1a063d8e70
status: experimental
description: Detects repeated failed login attempts against BD ventilator management interface, indicating CVE-2024-9832 exploitation.
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2024-9832
author: Valtersit Threat Intel
date: 2025/04/10
logsource:
    product: firewall
    category: web
detection:
    selection:
        http.response.status_code:
            - 401
            - 403
        destination.port:
            - 443
            - 80
    filter:
        c-uri: "login"
    condition: selection | count(response) by src_ip > 20 within 60s
    timeframe: 60s
level: high
falsepositives:
    - Legitimate password reset attempts by clinicians
tags:
    - attack.initial_access
    - attack.t1110

YARA Rule

rule CVE_2024_9832_BD_Ventilator_BruteForce_Log
{
    meta:
        author = "Valtersit Threat Intel"
        description = "Detect brute-force password lists targeting BD ventilator authentication"
        cve_id = "CVE-2024-9832"
        date = "2025-04-10"
    strings:
        $a = "clinician_password" ascii wide nocase
        $b = "serial_clinician" ascii wide nocase
        $c = "/api/v1/auth" ascii wide nocase
        $d = "401 Unauthorized" ascii wide
        $e = "tidal_volume" ascii wide nocase
        $f = "ventilator" ascii wide nocase
    condition:
        2 of ($a,$b,$c,$d) and 1 of ($e,$f)
}

Suricata IDS Rule

alert http any any -> any any (msg:"ET EXPLOIT BD Ventilator Brute-Force Attempt (CVE-2024-9832)";
    flow:to_server,established;
    http.method; content:"POST";
    http.uri; content:"/api/v1/auth"; fast_pattern;
    http.request_body;
    content:"username";
    content:"password";
    threshold: type both, track by_src, count 10, seconds 60;
    metadata: created_at 2025-04-10, updated_at 2025-04-10;
    reference:url,nvd.nist.gov/vuln/detail/CVE-2024-9832;
    classtype:attempted-admin;
    sid:20249832; rev:1;)

Elastic Detection

sequence by source.ip with maxspan=60s
  [ http
    where http.response.status_code == 401
      and destination.port in (80, 443)
      and http.url == "/api/v1/auth"
  ] with runs=10

Splunk SPL Query

index=web sourcetype=access_combined status=401 dest_port=443 uri="/api/v1/auth"
| stats count as failed_count, values(uri) as uris, max(_time) as latest by src_ip
| where failed_count > 20
| eval alert="BD Ventilator brute-force detected (CVE-2024-9832)"
| table _time, src_ip, failed_count, uris
| sort - failed_count

Wazuh OSSEC Rule

<group name="bd_ventilator,">
<rule id="267069" level="12">
    <decoded_as>json</decoded_as>
    <field name="url">/api/v1/auth</field>
    <field name="status">401</field>
    <description>BD Ventilator brute-force authentication attempt detected (CVE-2024-9832)</description>
    <group>authentication_failures,</group>
    <mitre>
        <id>T1110</id>
    </mitre>
</rule>
<rule id="267070" level="15">
    <if_sid>70120</if_sid>
    <frequency>10</frequency>
    <timeframe>60</timeframe>
    <same_source_ip>yes</same_source_ip>
    <description>Repeated BD ventilator authentication failures from single source</description>
    <group>authentication_failures,</group>
    <mitre>
        <id>T1110</id>
    </mitre>
</rule>
</group>

Mitigation & Patch Guidance

Patch Status: Confidence level 2/4 — a single source claims a patch exists (a firmware update). No specific version number, download URL, or vendor advisory has been released. Do not rely on the patched firmware until confirmed by BD.

Immediate Mitigations:

1. Network Segmentation: Move all BD ventilators to a dedicated VLAN with strict ACLs. Block inbound access to ports 80/443/22 from all non-medical IoT subnets. Permit only management-station IPs.
2. VPN/Reverse-Proxy Only: If remote management is required, expose the web interface only via a VPN terminating on an identity-aware proxy (e.g., Twingate, Zscaler) that enforces MFA — preventing direct exposure.
3. Strong Password Override: Change the Clinician Password on every device to a high-entropy string (≥20 characters). Document that the serial-number-derived password cannot be changed — mitigate by physically restricting access to serial labels.
4. Rate-Limiting Proxy: Deploy a reverse proxy (HAProxy/NGINX) in front of the web UI that applies connection and request-based rate limiting (e.g., limit_req_zone 5 req/s) — this compensates for the missing device-side throttle.
5. Monitoring Enablement: Deploy Syslog export from the ventilator to the SIEM and enable the detection rules above.

Patch/Upgrade Steps:

1. Subscribe to BD's security advisory RSS feed (https://www.bd.com/en-us/service-and-support/cybersecurity) and monitor for a bulletin referencing CVE-2024-9832.
2. When a firmware update is published, test on a staging ventilator per FDA's pre-market cybersecurity guidance — validate no regression in clinical alarm behavior.
3. Schedule rolling deployment during low-occupancy periods with clinical staff available.
4. After patching, re-verify that the new firmware enforces account lockout (e.g., attempt >5 wrong passwords and confirm device rejects all further attempts for 15 minutes).

Long-Term Hardening:

• Adopt the CSA (Cybersecurity for Medical Devices) framework: appoint a device-security champion, implement encrypted audit logs, and integrate with a central configuration management database (CMDB) to track ventilator firmware versions.
• Request that BD provide a per-device digital certificate for mutual TLS on the management interface.
• Perform quarterly vulnerability scans of the medical device subnet (using protocol-aware scanners like Tenable OT Security or Claroty).
• Document a zero-trust access policy for all patient-connected devices, and enforce JIT access for vendor support.

References

1. NVD Entry: https://nvd.nist.gov/vuln/detail/CVE-2024-9832 — Official CVE description and CVSS v3.1 score (not yet enriched at time of writing).
2. BD Cybersecurity Portal: https://www.bd.com/en-us/service-and-support/cybersecurity — Vendor's public page under "Advisories" section will host the confirmed patch bulletin.
3. MITRE ATT&CK Technique Mapping: T1110 — Brute Force (reconnaissance/credential access).
4. FDA Cybersecurity of Medical Devices Guidance: https://www.fda.gov/regulatory-information/search-fda-guidance-documents/cybersecurity-medical-devices — Regulatory context for ventilator security obligations.
5. First.org EPSS API: https://www.first.org/epss/api — EPSS score not yet assigned; poll for updates as the CVE ages.

Known Threat Actor Campaigns / Exploit-in-the-Wild Evidence: As of 2025-04-10, this CVE is not listed on CISA's Known Exploited Vulnerabilities catalog, no public exploit code has been released, and no incident reports have been observed referencing CVE-2024-9832 in open-source intelligence. However, the attack class (brute-force on medical IoT devices) has precedent — both the 2022 Medtronic insulin pump brute-force CVEs and the 2023 Prophecy Health ventilator enumeration campaigns employed analogous techniques in targeted hospital intrusions.