|2016-11-08||PLC||Phoenix Contact ILC 1xx||Matthias Niedermaier and Michael Kapfer ||N/A||CVE-2016-8366, CVE-2016-8371, CVE-2016-8380||N/A||N/A||N/A|
# Phoenix Contact ILC PLC Authentication Vulnerabilities
Matthias Niedermaier and Michael Kapfer of HSASec Hochschule Augsburg have identified authentication vulnerabilities in Phoenix Contact's ILC (inline controller) PLCs. Phoenix Contact GmbH & Co. KG has produced a mitigation plan that includes an update and recommended security practices to mitigate these vulnerabilities.
These vulnerabilities could be exploited remotely.
### AFFECTED PRODUCTS
Phoenix Contact reports that these vulnerabilities affect the following versions of ILC PLCs:
All ILC 1xx PLCs.
The identified vulnerabilities could allow an unauthenticated user to access human-machine interface (HMI) pages and to modify programmable logic controller (PLC) variables.
Impact to individual organizations depends on many factors that are unique to each organization. NCCIC/ICS-CERT recommends that organizations evaluate the impact of these vulnerabilities based on their operational environment, architecture, and product implementation.
Phoenix Contact GmbH & Co. KG is a German-based automation company.
The affected products, ILC 1xx PLCs, are inline controllers with an Ethernet interface for coupling to other controllers and systems. According to Phoenix Contact, ILC PLCs are deployed across several sectors including Commercial Facilities, Critical Manufacturing, Energy, and Water and Wastewater Systems. Phoenix Contact estimates that these products are used primarily in Europe, North America, and Asia.
### VULNERABILITY CHARACTERIZATION
# VULNERABILITY OVERVIEW
CLEARTEXT STORAGE OF SENSITIVE INFORMATION
Webvisit offers a password macro to protect HMI pages on the PLC against casual or coincidental opening of HMI pages by the user. The password macro can be configured in a way that the password is stored and transferred in clear text.
CVE-2016-8366 has been assigned to this vulnerability. A CVSS v3 base score of 7.3 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L).
AUTHENTICATION BYPASS ISSUES
The web server can be accessed without authenticating even if the authentication mechanism is enabled.
CVE-2016-8371 has been assigned to this vulnerability. A CVSS v3 base score of 7.3 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L).
ACCESS TO CRITICAL PRIVATE VARIABLE VIA PUBLIC METHOD
The web server allows access to read and write PLC variables without authentication.
CVE-2016-8380 has been assigned to this vulnerability. A CVSS v3 base score of 7.3 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L).
### VULNERABILITY DETAILS
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.
Phoenix Contact has released an update for Webvisit to mitigate the plaintext password storage issue. Users may obtain this update by contacting Phoenix Contact customer support at email@example.com, or +49 52 81/9 46 28 88 (Germany).
Connecting devices to a network via Ethernet always entails the risk of unauthorized access to the network. Phoenix Contact recommends that users implement an adequate defense-in-depth networking architecture (including the following) for control systems where these devices are operating:
oDevices should not be exposed to public networks without the use of virtual private networks (VPNs) for remote access.
oFirewalls should be used for network segmentation or controller isolation.
oAvailable communication channels or ports not needed in the application should be turned off. Administrators and users should check whether the application offers any option of deactivating active communication channels (e.g., SNMP, FTP, BootP, DCP), or setting passwords to prevent third parties from unauthorized accessing the controller and modifying the system.
oAccess to the devices should be limited to the fewest possible authorized personnel.
oChange standard or default passwords when first installing every component. Passwords should be changed in regular interval in order to reduce risks of becoming public. Passwords should have a maximum strength by the use of small and capital letters as well as numbers and special characters with a length of at least 10 characters.
oConduct regular thread analyses to discover whether current measures meet the safety requirements.
oInstall and maintain security software in order to defend new or recurring risks; such as viruses, Trojans, phishing attacks.
oUsers may decide to use the ILC 1x1 PLCs with the latest Firmware 4.42, because it offers the HTTPS protocol and HTML5 for the web server-based HMI system.
oWith regard to the controller's communication interfaces, Phoenix Contact recommends not to use the ILC 1xx controller in safety-critical applications unless using additional security devices.
For more information on this vulnerability and the associated update and mitigation strategies, please email Phoenix Contact at the following address: