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.

References

• https://nvd.nist.gov/vuln/detail/CVE-2021-20613
• https://jvn.jp/vu/JVNVU93268332/index.html
• https://www.cisa.gov/uscert/ics/advisories/icsa-22-013-07
• https://www.mitsubishielectric.com/en/psirt/vulnerability/pdf/2021-024_en.pdf