Rockwell Automation Micro800 and MicroLogix 1400 DoS vulnerability [CVE-2021-32926]
CVE number – CVE-2021-32926
Successful exploitation of this vulnerability may result in denial-of-service conditions, which may require a firmware flash to recover.
The following controllers are affected:
- Micro800: All versions
- MicroLogix 1400: Version 21 and later when Enhanced Password Security enabled
When an authenticated password change request takes place, this vulnerability could allow the attacker to intercept the message that includes the legitimate, new password hash and replace it with an illegitimate hash. The user would no longer be able to authenticate to the controller causing a denial-of-service condition.
Rockwell recommends confirming that setting and updating the password for the controller is done within a trusted network environment.
If this vulnerability is successfully exploited, the password can be reset by performing a firmware flash on the controller. Firmware flashing will put the controller into the default state and the user program and data will be lost.
Duncan is a technology professional with over 20 years experience of working in various IT roles. He has a interest in cyber security, and has a wide range of other skills in radio, electronics and telecommunications.