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ID

VDE-2019-022

Published

2019-12-16 10:00 (CET)

Last update

2019-12-16 10:00 (CET)

Vendor(s)

WAGO GmbH & Co. KG

Product(s)

Article No° Product Name Affected Version(s)
750-81xx/xxx-xxx (PFC100) < FW15
750-823 < FW15
750-82xx/xxx-xxx (PFC200) < FW15
750-831/xxx-xxx < FW15
750-832/xxx-xxx < FW15
750-852 < FW15
750-852 < FW15
750-862 < FW15
750-880/xxx-xxx < FW15
750-881 < FW15
750-889 < FW15
750-890/xxx-xxx < FW15
750-891 < FW15

Summary

The reported vulnerabilities allow a remote attacker to change the setting, delete the application, set the device to factory defaults, code execution and to cause a system crash or denial of service.

Note(s)

The following products are affected by the listed vulnerabilities:

Series PFC100 (750-81xx/xxx-xxx)
Series PFC200 (750-82xx/xxx-xxx)

The following products are affected by the vulnerability CVE-2019-5078

750-852, 750-831/xxx-xxx, 750-881, 750-880/xxx-xxx, 750-889
750-823, 750-832/xxx-xxx, 750-862, 750-890/xxx-xxx, 750-891

 

Vulnerabilities



Last Update
Feb. 18, 2020, 1:34 p.m.
Weakness
Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119)
Summary
An exploitable stack buffer overflow vulnerability exists in the command line utility getcouplerdetails of WAGO PFC200 Firmware versions 03.01.07(13) and 03.00.39(12), and WAGO PFC100 Firmware version 03.00.39(12). A specially crafted set of packets sent to the iocheckd service "I/O-Check" can cause a stack buffer overflow in the sub-process getcouplerdetails, resulting in code execution. An attacker can send unauthenticated packets to trigger this vulnerability.
Last Update
Feb. 18, 2020, 1:34 p.m.
Weakness
Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') (CWE-120)
Summary
An exploitable heap buffer overflow vulnerability exists in the iocheckd service ''I/O-Chec'' functionality of WAGO PFC 200 Firmware version 03.01.07(13) and 03.00.39(12), and WAGO PFC100 Firmware version 03.00.39(12). A specially crafted set of packets can cause a heap buffer overflow, potentially resulting in code execution. An attacker can send unauthenticated packets to trigger this vulnerability.
Last Update
Feb. 18, 2020, 1:34 p.m.
Weakness
Out-of-bounds Write (CWE-787)
Summary
An exploitable heap buffer overflow vulnerability exists in the iocheckd service "I/O-Check" functionality of WAGO PFC200 Firmware versions 03.01.07(13) and 03.00.39(12), and WAGO PFC100 Firmware version 03.00.39(12). A specially crafted set of packets can cause a heap buffer overflow, potentially resulting in code execution. An attacker can send unauthenticated packets to trigger this vulnerability.
Last Update
Feb. 18, 2020, 1:32 p.m.
Weakness
Out-of-bounds Write (CWE-787)
Summary
An exploitable heap buffer overflow vulnerability exists in the iocheckd service I/O-Check functionality of WAGO PFC200 Firmware version 03.01.07(13), WAGO PFC200 Firmware version 03.00.39(12), and WAGO PFC100 Firmware version 03.00.39(12). A specially crafted set of packets can cause a heap buffer overflow, potentially resulting in code execution. An attacker can send unauthenticated packets to trigger this vulnerability.
Last Update
Feb. 18, 2020, 1:34 p.m.
Weakness
Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') (CWE-120)
Summary
An exploitable stack buffer overflow vulnerability exists in the iocheckd service ''I/O-Check'' functionality of WAGO PFC200 Firmware version 03.01.07(13), WAGO PFC200 Firmware version 03.00.39(12) and WAGO PFC100 Firmware version 03.00.39(12). A specially crafted set of packets can cause a stack buffer overflow, resulting in code execution. An attacker can send unauthenticated packets to trigger this vulnerability.
Last Update
Feb. 18, 2020, 1:36 p.m.
Weakness
Missing Authentication for Critical Function (CWE-306)
Summary
An exploitable denial of service vulnerability exists in the iocheckd service "I/O-Check" functionality of WAGO PFC200 Firmware versions 03.01.07(13) and 03.00.39(12), and WAGO PFC100 Firmware version 03.00.39(12). A specially crafted set of packets can cause a denial of service, resulting in the device entering an error state where it ceases all network communications. An attacker can send unauthenticated packets to trigger this vulnerability.
Last Update
Feb. 18, 2020, 1:34 p.m.
Weakness
Information Exposure (CWE-200)
Summary
An exploitable information exposure vulnerability exists in the iocheckd service "I/O-Check" functionality of WAGO PFC200 Firmware versions 03.01.07(13) and 03.00.39(12), and WAGO PFC100 Firmware version 03.00.39(12). A specially crafted set of packets can cause an external tool to fail, resulting in uninitialized stack data to be copied to the response packet buffer. An attacker can send unauthenticated packets to trigger this vulnerability.

Impact

These vulnerabilities allow an attacker to manipulate the settings or disturb the basic function of the device via specially crafted IP packets. This can be potentially used to get control of the device.

Solution

The I/O-Check service protocol is only needed during installation and commissioning, not during normal operations. It is highly recommended to disable the IP-port 6626 after commissioning. This is the easiest and securest way to protect your device for the listed vulnerabilities and for upcoming zero day exploits.

Regardless of the action described above, the following CVEs can be fixed alternatively by a firmware update >= FW 15.

CVE-2019-5073
CVE-2019-5074
CVE-2019-5075
CVE-2019-5079
CVE-2019-5081
CVE-2019-5082

Mitigation

  • Restrict network access to the device.
  • Do not directly connect the device to the internet.
  • Disable unused TCP/UDP-ports

Reported by

This vulnerability was reported by Kelly Leuschner of Cisco Talos to WAGO coordinated by CERT@VDE.