Unsecured Signals: Vodafone H500s WiFi Password Exposed via Unauthenticated Endpoint (CVE-2022-4985)

Overview

CVE-2022-4985 details a significant security vulnerability affecting Vodafone H500s devices running firmware v3.5.10 (hardware model Sercomm VFH500). This flaw allows unauthenticated remote attackers to retrieve the WiFi access point password by sending a crafted HTTP GET request. This unauthorized access can compromise the confidentiality of network traffic and any attached systems, leading to potential data breaches and other malicious activities.

Technical Details

The vulnerability resides in the /data/activation.json endpoint. By sending a specifically crafted HTTP GET request to this endpoint with certain headers and cookies, an attacker can retrieve a JSON document. This document contains the wifi_password field, which stores the WiFi password in plaintext. The lack of authentication requirements for accessing this endpoint is the root cause of the vulnerability. An example request would look something like this:

      
        GET /data/activation.json HTTP/1.1
        Host: [Router IP Address]
        User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/96.0.4664.110 Safari/537.36
        Accept: application/json, text/plain, */*
        Accept-Language: en-US,en;q=0.5
        Accept-Encoding: gzip, deflate
        Connection: close
      
    

CVSS Analysis

Due to the details provided, a CVSS score cannot be calculated. However, the characteristics of this vulnerability can be assessed:

• Attack Vector (AV): Network (N) – The vulnerability is exploitable over a network.
• Attack Complexity (AC): Low (L) – Exploitation requires minimal effort.
• Privileges Required (PR): None (N) – No privileges are required to exploit the vulnerability.
• User Interaction (UI): None (N) – No user interaction is required.
• Scope (S): Unchanged (U) – The vulnerability does not impact resources beyond the scope of the vulnerable component.
• Confidentiality Impact (C): High (H) – The WiFi password is exposed.
• Integrity Impact (I): None (N) – The vulnerability does not directly impact integrity.
• Availability Impact (A): None (N) – The vulnerability does not directly impact availability.

This suggests a high severity vulnerability based on the ability to gain unauthorized network access without authentication.

Possible Impact

Successful exploitation of CVE-2022-4985 can have severe consequences:

• Unauthorized Network Access: Attackers can gain full access to the wireless network, bypassing security measures.
• Data Theft: Sensitive data transmitted over the network can be intercepted and stolen.
• Malware Distribution: The compromised network can be used to distribute malware to connected devices.
• Lateral Movement: Attackers can use the compromised network as a launchpad to access other systems on the network.
• Denial-of-Service (DoS) Attacks: The network can be used to launch DoS attacks against external targets.

Mitigation or Patch Steps

The primary mitigation step is to update the firmware of the Vodafone H500s router to a version that addresses this vulnerability. Users should:

1. Check for Firmware Updates: Access the router’s web interface and navigate to the firmware update section. Follow the instructions to download and install the latest available firmware.
2. Contact Vodafone Support: If a firmware update is not available, contact Vodafone support to inquire about the availability of a patch or a replacement device.
3. Disable Remote Administration (If Possible): If the router offers the option to disable remote administration, disable it to reduce the attack surface.
4. Use a Strong and Unique WiFi Password: Even if the vulnerability is not immediately patched, using a strong and unique WiFi password can make it more difficult for attackers to exploit the vulnerability.
5. Monitor Network Traffic: Monitor network traffic for suspicious activity, such as unauthorized access attempts or unusual data transfers.