Rockwell Automation has recommended fixes for an uncontrolled resource consumption and stack-based buffer overflow vulnerabilities in its CompactLogix 5370, according to a report with NCCIC.
Successful exploitation of these remotely exploitable vulnerabilities, discovered by could allow a remote attacker to render the web server unavailable and/or place the controller in a major non-recoverable faulted state (MNRF).
Younes Dragoni of Nozomi Networks reported these vulnerabilities to NCCIC. David Atch of CyberX reported CVE-2019-10954 to NCCIC.
The following versions of CompactLogix 5370, a programmable automation controller, suffer from the issues:
• CompactLogix 5370 L1 controllers Version 20 to 30.014 and earlier
• CompactLogix 5370 L2 controllers Versions 20 to 30.014 and earlier
• CompactLogix 5370 L3 controllers Versions 20 to 30.014 and earlier
• Compact GuardLogix 5370 controllers Versions 20 to 30.014 and earlier
• Armor Compact GuardLogix 5370 controllers, Versions 20 to 30.014 and earlier
In one vulnerability, an attacker could send a crafted HTTP/HTTPS request to render the web server unavailable and/or lead to remote code execution caused by a stack-based buffer overflow vulnerability. A cold restart is required for recovering the system.
CVE-2019-10952 is the case number assigned to this vulnerability, which has a CVSS v3 base score of 5.3.
In addition, an attacker could send crafted SMTP packets to cause a denial-of-service condition where the controller enters a major non-recoverable faulted state (MNRF).
CVE-2019-10954 is the case number assigned to this vulnerability, which has a CVSS v3 base score of 8.6 .
The products see use mainly in the critical manufacturing sector. They also see action on a global basis.
No known public exploits specifically target these vulnerabilities. However, an attacker with low skill level could leverage the vulnerabilities.
Rockwell recommends the following:
• Rockwell Automation encourages users to apply the latest available version of firmware to keep up to date with the latest features, anomaly fixes, and security improvements. Update to a version of firmware as listed below that mitigates the associated risk:
Apply FRN 31.011 or later
• For EtherNet/IP-based vulnerabilities (ID 1-14), block all traffic to and from outside the manufacturing zone by blocking or restricting access to Port 2222/TCP/UDP and Port 44818/TCP/UDP using proper network infrastructure controls, such as firewalls, UTM devices, or other security appliances. For more information on TCP/UDP ports used by Rockwell Automation Products, see Knowledgebase Article ID 898270 (login required).
o Stratix users can use Device Manager or Studio 5000 Logix Designer to configure access control lists (ACL) to block/restrict ports. See section “Access Control Lists” in Stratix Managed Switches User Manual, publication 1783-UM007, for detailed instructions.
• For web-based vulnerabilities (ID 15-17), block all traffic from outside the manufacturing zone by blocking or restricting access to Port 80/443/TCP.
o Stratix users can use Device Manager or Studio 5000 Logix Designer to configure ACL’s to block/restrict ports. See section “Access Control Lists” in Stratix Managed Switches User Manual, publication 1783-UM007, for detailed instructions.
• Utilize proper network infrastructure controls, such as firewalls, to help ensure SMTP packets from unauthorized sources are blocked.
• Consult the product documentation for specific features, such as a hardware key-switch setting, which may be used to block unauthorized changes, etc.
• Use trusted software, software patches, and antivirus/antimalware programs and interact only with trusted websites and attachments.
• Minimize network exposure for all control system devices and/or systems, and ensure they are not accessible from the Internet. For further information about the risks of unprotected Internet accessible control systems, please see Knowledgebase Article ID 494865 (login required).
• 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 a VPN is only as secure as the connected devices.
For more information refer to Rockwell’s Security Advisory (login required).