Accuenergy Acuvim II Authentication Vulnerabilities

OVERVIEW

This advisory was originally posted to the US-CERT secure Portal library on October 2, 2014, and is being released to the ICS-CERT web site.

Independent researcher Laisvis Lingvevicius has identified two authentication vulnerabilities within the Accuenergy AXM-NET Ethernet module’s web server. The AXM-NET Ethernet module is an accessory for the Acuvim II. Accuenergy has produced a firmware upgrade that mitigates these vulnerabilities. The researcher has tested the firmware to validate that it resolves the vulnerabilities.

These vulnerabilities could be exploited remotely.

AFFECTED PRODUCTS

The following Accuenergy Acuvim II accessory is affected:

• AXN-NET Ethernet module v.3.04 

IMPACT

The authentication bypass vulnerability allows access to the settings on the Ethernet module web server interface without authenticating. The password bypass vulnerability allows an attacker to display passwords using JavaScript. A malicious user could create a denial of service for the web server by changing the network settings.

Impact to individual organizations depends on many factors that are unique to each organization. ICS-CERT recommends that organizations evaluate the impact of these vulnerabilities based on their operational environment, architecture, and product implementation.

Accuenergy is a Canada-based company that maintains offices in several countries around the world, including the United States, Canada, and China.

The affected product, Acuvim II, is a multifunction power metering device. The AXM-NET Ethernet module creates a web page to display data produced by the Acuvim II. According to Accuenergy, Acuvim II is deployed in the Energy sector. Accuenergy estimates that this product is used primarily in North America and China.

VULNERABILITY CHARACTERIZATION

VULNERABILITY OVERVIEW

By accessing a specific uniform resource locator (URL) on the web server, a malicious user is able to access settings without authenticating. Accessible settings are limited, and include the network settings for the AXM-NET module web server, but not the Acuvim II device.

CVE-2014-2373NVD, http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2014-2373, NIST uses this advisory to create the CVE web site report.  has been assigned to this vulnerability. A CVSS v2 base score of 7.5 has been assigned; the CVSS vector string is (AV:N/AC:L/Au:N/C:P/I:P/A:P).CVSS Calculator, http://nvd.nist.gov/cvss.cfm?version=2&vector=AV:N/AC:L/Au:N/C:P/I:P/A:P, web site last accessed October 30, 2014.

The Acuvim II uses JavaScript to validate passwords leaving it vulnerable to a JavaScript attack that displays passwords. Authenticated users could change the network settings of the AXM-NET module web server, but do not have access to the Acuvim II device.

CVE-2014-2374NVD, http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2014-2374, NIST uses this advisory to create the CVE web site report. has been assigned to this vulnerability. A CVSS v2 base score of 7.5 has been assigned; the CVSS vector string is (AV:N/AC:L/Au:N/C:P/I:P/A:P). CVSS Calculator, http://nvd.nist.gov/cvss.cfm?version=2&vector=AV:N/AC:L/Au:N/C:P/I:P/A:P, web site last accessed October 30, 2014.

VULNERABILITY DETAILS

EXPLOITABILITY

These vulnerabilities could be exploited remotely.

EXISTENCE OF EXPLOIT

No known public exploits specifically target these vulnerabilities.

An attacker with a low skill would be able to exploit these vulnerabilities.

MITIGATION

Accuenergy has produced a patch to mitigate these vulnerabilities. The patch can be downloaded at the following location:

http://www.accuenergy.com/firmware-update-axm-net

ICS-CERT encourages asset owners to take additional defensive measures to protect against this and other cybersecurity risks.

• Minimize network exposure for all control system devices and/or systems, and ensure that they are not accessible from the Internet.
• Locate control system networks and remote devices behind firewalls, and isolate them from the business network.
• When remote access is required, use secure methods, such as Virtual Private Networks (VPNs), recognizing that VPNs may have vulnerabilities and should be updated to the most current version available. Also recognize that VPN is only as secure as the connected devices.

ICS-CERT also provides a section for control systems security recommended practices on the ICS-CERT web page at http://ics-cert.us-cert.gov/content/recommended-practices. Several recommended practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies. ICS-CERT reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.

Additional mitigation guidance and recommended practices are publicly available in the ICS‑CERT Technical Information Paper, ICS-TIP-12-146-01B—Targeted Cyber Intrusion Detection and Mitigation Strategies, that is available for download from the ICS-CERT web site (www.ics-cert.org).

Organizations observing any suspected malicious activity should follow their established internal procedures and report their findings to ICS-CERT for tracking and correlation against other incidents.

In addition, ICS-CERT recommends that users take the following measures to protect themselves from social engineering attacks:

1. Do not click web links or open unsolicited attachments in email messages.

2. Refer to Recognizing and Avoiding Email ScamsRecognizing and Avoiding Email Scams, http://www.us-cert.gov/reading_room/emailscams_0905.pdf, web site last accessed October 30, 2014. for more information on avoiding email scams.

3. Refer to Avoiding Social Engineering and Phishing AttacksNational Cyber Alert System Cyber Security Tip ST04-014, http://www.us-cert.gov/cas/tips/ST04-014.html, web site last accessed October 30, 2014.  for more information on social engineering attacks.

• Accuenergy