ICS Advisory

B+B SmartWorx VESP211 Authentication Bypass Vulnerability

Last Revised
Alert Code
ICSA-16-049-01

OVERVIEW

Independent researcher Maxim Rupp has identified an authentication bypass vulnerability in B+B SmartWorx’s VESP211 serial servers. B+B SmartWorx has produced an implementation plan to mitigate this vulnerability.

This vulnerability could be exploited remotely.

AFFECTED PRODUCTS

The following VESP211 serial servers are affected:

  • Model: VESP211-EU       Firmware Version: 1.7.2,
  • Model: VESP211-232      Firmware Version: 1.7.2, and
  • Model: VESP211-232      Firmware Version: 1.5.1

IMPACT

Successful exploitation of this vulnerability may allow attackers to perform administrative operations over the network without authentication.

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

BACKGROUND

B+B SmartWorx is a US-based company that has additional offices located in Ireland and the Czech Republic. In January, B+B SmartWorx merged with Advantech, a Taiwan-based company.

The affected products, VESP211 serial servers, are an interface for connecting serial devices to an Ethernet network. According to B+B SmartWorx, the VESP211 serial servers are deployed across several sectors including Energy, Telecommunications, and Transportation. B+B SmartWorx estimates that these products are used primarily in North America with a smaller percentage in Europe and South America.

VULNERABILITY CHARACTERIZATION

VULNERABILITY OVERVIEW

USE OF CLIENT-SIDE AUTHENTICATIONCWE-603: Use of Client-Side Authentication, http://cwe.mitre.org/data/definitions/603.html, web site last accessed February 18, 2016.

Web interface uses JavaScript to check for client authentication and redirect unauthorized users to a login page. By intercepting and change requests, an unauthenticated user may bypass authentication and access restricted pages.

CVE-2016-2275NVD, http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-2275, NIST uses this advisory to create the CVE web site report. This web site will be active sometime after publication of this advisory. has been assigned to this vulnerability. A CVSS v3 base score of 9.8 has been assigned; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).CVSS Calculator, https://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H, web site last accessed February 18, 2016.

VULNERABILITY DETAILS

EXPLOITABILITY

This vulnerability could be exploited remotely.

EXISTENCE OF EXPLOIT

No known public exploits specifically target this vulnerability.

DIFFICULTY

An attacker with a low skill would be able to exploit this vulnerability.

MITIGATION

Advantech/B+B recommends the VESP211 serial servers only be operated behind a local network firewall.

ICS-CERT recommends that users take defensive measures to minimize the risk of exploitation of these vulnerabilities. Specifically, users should:

  • Minimize network exposure for all control system devices and/or systems, and ensure that they are not accessible from the Internet.
  • 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 reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.

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.

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 (http://ics-cert.us-cert.gov/).

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.

This product is provided subject to this Notification and this Privacy & Use policy.

Vendor

B+B SmartWorx