CVE-2021-20613: Mitsubishielectric FX3U-Enet-L Firmware

High severity, CVSS 7.5. EPSS: 3.6% chance of exploitation in the next 30 days.

Improper initialization vulnerability in MELSEC-F series FX3U-ENET Firmware version 1.16 and prior, FX3U-ENET-L Firmware version 1.16 and prior and FX3U-ENET-P502 Firmware version 1.16 and prior allows a remote unauthenticated attacker to cause a denial-of-service (DoS) condition in communication function of the product by sending specially crafted packets. Control by MELSEC-F series PLC is not affected by this vulnerability, but system reset is required for recovery.

Affected products

• Mitsubishielectric FX3U-Enet-L Firmware: up to and including 1.16
• Mitsubishielectric FX3U-Enet-p502 Firmware: up to and including 1.16
• Mitsubishielectric FX3U-Enet Firmware: up to and including 1.16

Published 2022-01-14. Last modified 2026-06-17.