CVE-2021-20597: Mitsubishielectric r08psfcpu Firmware

Critical severity, CVSS 9.1. EPSS: 2.2% chance of exploitation in the next 30 days.

Insufficiently Protected Credentials vulnerability in Mitsubishi Electric MELSEC iQ-R series Safety CPU modules R08/16/32/120SFCPU firmware versions "26" and prior and Mitsubishi Electric MELSEC iQ-R series SIL2 Process CPU modules R08/16/32/120PSFCPU firmware versions "11" and prior allows a remote unauthenticated attacker to login to the target unauthorizedly by sniffing network traffic and obtaining credentials when registering user information in the target or changing a password.

Affected products

• Mitsubishielectric r08psfcpu Firmware: any version
• Mitsubishielectric r08sfcpu Firmware: any version
• Mitsubishielectric r120psfcpu Firmware: any version
• Mitsubishielectric r120sfcpu Firmware: any version
• Mitsubishielectric r16psfcpu Firmware: any version
• Mitsubishielectric r16sfcpu Firmware: any version
• Mitsubishielectric r32psfcpu Firmware: any version
• Mitsubishielectric r32sfcpu Firmware: any version

Published 2021-08-06. Last modified 2026-06-17.