CVE-2024-32946

Executive Summary

CVE-2024-32946 exposes a critical weakness in the LevelOne WBR-6012 router (firmware version R0.40e6) where sensitive information is transmitted in cleartext over Web and FTP services. This vulnerability allows an attacker on the same network segment to perform network sniffing and capture credentials, session tokens, or other confidential data. The lack of encryption (HTTPS/FTPS) makes the device highly susceptible to passive eavesdropping attacks. With a CVSS score of 5.9, this is a medium-severity issue that requires immediate attention, especially in environments where the router is used for sensitive communications.

CVSS Breakdown & Threat Level

• Attack Vector (AV): Adjacent Network (AV:A) – The attacker must be on the same local network or wireless range.
• Attack Complexity (AC): Low (AC:L) – No special conditions required; standard network sniffing tools suffice.
• Privileges Required (PR): None (PR:N) – No authentication needed to intercept traffic.
• User Interaction (UI): None (UI:N) – The victim does not need to perform any action.
• Scope (S): Unchanged (S:U) – The vulnerability does not affect other components.
• Confidentiality (C): High (C:H) – Cleartext transmission exposes all sensitive data.
• Integrity (I): None (I:N) – No data modification possible via this vector.
• Availability (A): None (A:N) – No denial-of-service impact.

Threat Level: Medium (5.9) – Exploitation is straightforward but requires network proximity.

Deep Dive & Mechanics

The LevelOne WBR-6012 router’s web management interface and FTP service transmit data over unencrypted channels (HTTP and FTP). This means that any user credentials, configuration details, or other sensitive information sent to or from the router are sent as plaintext. An attacker with access to the same network (e.g., via Wi-Fi or a compromised switch) can use packet capture tools (e.g., Wireshark, tcpdump) to intercept this traffic. The vulnerability is rooted in the firmware’s failure to enforce TLS/SSL encryption for administrative and file transfer services.

Attack Flow:

1. Attacker connects to the same local network as the target router.
2. Attacker enables promiscuous mode on their network interface and starts capturing packets.
3. When an administrator logs into the router’s web interface or uses FTP, the credentials and data are transmitted in cleartext.
4. Attacker extracts the captured data using simple filters (e.g., http.request or ftp in Wireshark).

Vulnerable vs. Patched Code

No patched version is available. The vulnerable code is the entire firmware R0.40e6, which lacks encryption for Web and FTP services. A hypothetical patch would involve:

• Replacing HTTP with HTTPS using a self-signed or trusted certificate.
• Replacing FTP with FTPS (FTP over SSL/TLS) or SFTP.
• Enforcing encryption for all administrative interfaces.

Vulnerable Code Snippet (Conceptual):

# Example of vulnerable HTTP server configuration
http_server = SimpleHTTPServer()
http_server.serve_forever()  # No TLS

Patched Code Snippet (Conceptual):

# Example of patched HTTPS server configuration
import ssl
http_server = SimpleHTTPServer()
context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
context.load_cert_chain('cert.pem', 'key.pem')
http_server.socket = context.wrap_socket(http_server.socket, server_side=True)
http_server.serve_forever()

Exploitation & Lab Setup

Red Team

Lab Environment:

• Target: LevelOne WBR-6012 router (firmware R0.40e6) connected to a local network.
• Attacker: Kali Linux machine on the same network segment.
• Tools: Wireshark, tcpdump, or bettercap.

Exploitation Steps:

1. Connect the attacker machine to the same network as the router.
2. Start packet capture:

   sudo tcpdump -i eth0 -w capture.pcap
   

3. Wait for an administrator to log into the router’s web interface (e.g., http://192.168.1.1) or use FTP.
4. Analyze the capture file:

   tshark -r capture.pcap -Y "http.request or ftp" -T fields -e http.host -e http.request.uri -e ftp.request.command
   

5. Extract cleartext credentials from the output.

Example Output:

192.168.1.1 /login.cgi?username=admin&password=secret123
USER admin
PASS secret123

Blue Team

Detection & Prevention:

• Monitor network traffic for unencrypted HTTP and FTP traffic to the router’s IP address.
• Use network segmentation to isolate the router from untrusted devices.
• Implement a firewall rule to block FTP (port 21) and HTTP (port 80) from external networks.
• Deploy an IDS/IPS to alert on cleartext credential transmission.

Hunting Query:

-- Example for a SIEM (e.g., Splunk)
index=network sourcetype=packet
| search dest_ip=192.168.1.1 (port=80 OR port=21)
| table _time, src_ip, dest_ip, protocol, payload

Indicators of Compromise (IOCs)

• Network IOCs:
  • Unencrypted HTTP requests to the router’s IP on port 80.
  • FTP login attempts (USER/PASS commands) on port 21.
  • Presence of http.request or ftp packets in network captures.
• File IOCs:
  • PCAP files containing cleartext credentials.
• Behavioral IOCs:
  • Repeated failed login attempts followed by successful cleartext capture.

Detection Engineering

YARA Rule

rule CVE_2024_32946_Cleartext_Credentials {
    meta:
        description = "Detects cleartext credentials in network traffic for LevelOne WBR-6012"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2024-32946"
    strings:
        $http_cred = /(username|password)=[^&\s]+/ nocase
        $ftp_user = /USER [^\r\n]+/
        $ftp_pass = /PASS [^\r\n]+/
    condition:
        any of them
}

Sigma Rule

title: Cleartext Credentials in LevelOne WBR-6012 Traffic
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects unencrypted HTTP and FTP traffic containing credentials to a LevelOne WBR-6012 router.
author: Valters IT
date: 2025/04/10
logsource:
    category: network
    product: suricata
detection:
    selection:
        dest_port:
            - 80
            - 21
        payload|contains:
            - 'username='
            - 'password='
            - 'USER '
            - 'PASS '
    condition: selection
falsepositives:
    - Legitimate unencrypted traffic to other devices (rare)
level: high

Suricata Rule

alert tcp any any -> any 80 (msg:"CVE-2024-32946 - Cleartext HTTP Credentials to LevelOne WBR-6012"; content:"username="; nocase; content:"password="; nocase; sid:1000001; rev:1;)
alert tcp any any -> any 21 (msg:"CVE-2024-32946 - Cleartext FTP Credentials to LevelOne WBR-6012"; content:"USER "; nocase; content:"PASS "; nocase; sid:1000002; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Isolate the router: Place it on a separate VLAN with restricted access.
2. Disable FTP: If not required, disable the FTP service via the router’s admin interface.
3. Use VPN: Access the router’s web interface only through a VPN tunnel to encrypt traffic.
4. Monitor logs: Enable logging and monitor for cleartext traffic.

Long-Term Fix:

• Vendor Patch: Contact LevelOne for a firmware update that enables HTTPS and FTPS. If unavailable, consider replacing the device with a secure alternative.
• Network Segmentation: Implement strict network segmentation to limit exposure.
• Encryption Enforcement: Use a reverse proxy (e.g., Nginx with SSL) in front of the router to terminate HTTPS and forward to the router’s HTTP interface.

Workaround:

• Use SSH tunneling to access the router’s web interface:

  ssh -L 8080:192.168.1.1:80 user@jumphost
  

  Then access http://localhost:8080 over an encrypted SSH connection.

Valters IT
Securing Digital Frontiers