Siemens BACnet Field Panels
ICSA： ICS Advisory (ICSA-17-285-05)
CVSS v3 7.5
ATTENTION: Remotely exploitable/low skill level to exploit.
Equipment: BACnet Field Panels
Vulnerabilities: Authentication Bypass Using an Alternate Path or Channel, Path Traversal
Siemens reports that the vulnerabilities affect the following BACnet field panels:
- APOGEE PXC BACnet Automation Controllers: All versions prior to V3.5
- TALON TC BACnet Automation Controllers: All versions prior to V3.5
Successful exploitation of these vulnerabilities could allow unauthenticated attackers with access to the integrated webserver to download sensitive information.
Siemens has provided firmware Version V3.5 for BACnet Field Panels Advanced modules, which fixes the vulnerabilities, and they recommend that users update to the new fixed version. Users should contact the local service organization for further information on how to obtain and apply V3.5. The web form is available at the following location on the Siemens web site:
For more information on this vulnerability and more detailed mitigation instructions, please see Siemens Security Advisory SSA-148078 at the following location:
NCCIC/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.
- 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 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. 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.
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.
No known public exploits specifically target these vulnerabilities.
An attacker with network access to the integrated web server (Ports 80/TCP and 443/TCP) could bypass the authentication and download sensitive information from the device.
A directory traversal vulnerability could allow a remote attacker with network access to the integrated web server (Ports 80/TCP and 443/TCP) to obtain information on the structure of the file system of the affected devices.
Siemens reported these vulnerabilities to ICS-CERT.
Critical Infrastructure Sector: Commercial facilities
Countries/Areas Deployed: Worldwide
Company Headquarters Location: Germany