An attacker needs an authorized login with administrative privileges on the device in order to exploit the herein mentioned vulnerability.
The weakness allows an attacker which has admin privileges on the device to redirect to his own Azure cloud account and install malicious software with the firmware update functionality.
The firmware update package (WUP) is not signed entirely. The used password offers no additional security, it is just meant to protect from unintentional modifications of the WUP file. Thus only the integrity of the signed firmware part (rauc file) is protected against intended manipulation. An attacker could manipulate the WUP file in a way that additional files with potentially malicious content are added to the WUP file.
In case an authorized user that issues a firmware update could be tricked into installing this manipulated WUP file onto the device, the potentially malicious files would also be copied and installed on to the device and executed with elevated privileges.
The Cloud Connectivity of the WAGO PLCs is used to connect the device with the cloud services from different providers. It also supports maintenance functionality with the firmware update function from the WAGO cloud.
An attacker needs an authorized login with administrative privileges on the device in order to exploit the mentioned vulnerabilities.
The Web-Based Management (WBM) of WAGOs programmable logic controller (PLC) is typically used for commissioning and update. The controller is an embedded device which has limited resources. The vulnerability described here takes advantage of this fact.
With special crafted requests it is possible to have a denial of service of the WBM.
With special crafted requests it is possible to get sensitive information, in this case the password hashes, by measuring response delay. With a substantial amount of time this data can be used to calculate the passwords of the Web-Based Management users. In case of CVE 2019-5134 , the password salt can also be extracted.
The communication between e!Cockpit and the programmable logic controller is not encrypted. The broken cryptographic algorithm allows an attacker to decode the password for the e!Cockpit communication and with this to manipulate the application.
The password used by e!Cockpit for authentication against the PLC is encrypted with a hard- coded key. An attacker is able to decrypt the password by listening to the network traffic.
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
The reported vulnerability allows a remote attacker to check paths and file names that are used in filesystem operations.
Update, 18.9.2019, 18:30