CVE-2021-20596: Mitsubishielectric FX3U-Enet-L Firmware

High severity, CVSS 7.5. EPSS: 2.2% chance of exploitation in the next 30 days.

NULL Pointer Dereference in MELSEC-F Series FX3U-ENET firmware version 1.14 and prior, FX3U-ENET-L firmware version 1.14 and prior and FX3U-ENET-P502 firmware version 1.14 and prior allows a remote unauthenticated attacker to cause a DoS condition in communication by sending specially crafted packets. Control by MELSEC-F series PLC is not affected and system reset is required for recovery.

Affected products

• Mitsubishielectric FX3U-Enet-L Firmware: up to and including 1.14
• Mitsubishielectric FX3U-Enet-p502 Firmware: up to and including 1.14
• Mitsubishielectric FX3U-Enet Firmware: up to and including 1.14

Published 2021-07-22. Last modified 2026-06-17.