{"id":"CVE-2021-20613","aliases":["EUVD-2021-8031","GHSA-4mv5-vjxv-hh3h"],"status":"published","title":"Improper initialization vulnerability in MELSEC-F series FX3U-ENET Firmware version 1.16 and...","description":"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.","severity":{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-10","score":0.03823,"percentile":0.90161,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-665"],"published":"2022-01-14T19:04:47Z","modified":"2026-06-17T03:34:07Z","products":[{"vendor":"mitsubishielectric","product":"fx3u-enet-l_firmware"},{"vendor":"mitsubishielectric","product":"fx3u-enet-p502_firmware"},{"vendor":"mitsubishielectric","product":"fx3u-enet_firmware"}],"references":[{"url":"https://jvn.jp/vu/JVNVU93268332/index.html","tags":["x_refsource_MISC","x_transferred","Third Party Advisory","VDB Entry"]},{"url":"https://www.mitsubishielectric.com/en/psirt/vulnerability/pdf/2021-024_en.pdf","tags":["x_refsource_MISC","x_transferred","Vendor Advisory"]},{"url":"https://www.cisa.gov/uscert/ics/advisories/icsa-22-013-07","tags":["x_refsource_MISC","x_transferred","Third Party Advisory","US Government Resource"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-20613"},{"url":"https://github.com/advisories/GHSA-4mv5-vjxv-hh3h"}],"sources":{"cve":[{"id":"CVE-2021-20613","description":"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.","status":"published","published":"2022-01-14T19:04:47Z","modified":"2024-08-03T17:45:44.677Z","updated_at":"2026-11-02T14:32:55.564736Z"}],"euvd":[{"id":"EUVD-2021-8031","description":"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.","status":"published","published":"2022-01-14T19:04:47Z","modified":"2024-08-03T17:45:44Z","updated_at":"2026-11-03T03:25:08.888273Z"}],"ghsa":[{"id":"GHSA-4mv5-vjxv-hh3h","title":"Improper initialization vulnerability in MELSEC-F series FX3U-ENET Firmware version 1.16 and...","description":"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.","status":"published","published":"2022-01-15T00:01:33Z","modified":"2023-02-03T05:04:53Z","cwes":["CWE-665"],"updated_at":"2026-11-02T14:53:38.626767Z"}],"nvd":[{"id":"CVE-2021-20613","description":"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.","status":"published","published":"2022-01-14T20:15:09.91Z","modified":"2026-06-17T03:34:07.593Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"},{"version":"2.0","score":7.8,"vector":"AV:N/AC:L/Au:N/C:N/I:N/A:C","level":"high","assessor":"primary"}],"cwes":["CWE-665"],"updated_at":"2026-11-02T14:07:03.821385Z"}]}}