CVE-2021-20596

HighCVSS 7.5/10Last modified Jun 17, 2026

Description

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.

Metrics

CVSS 3.1 7.5/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness enumeration

CWE-476

Affected software

No affected versions have been published.

Timeline

Published
Jul 22, 2021
Last modified
Jun 17, 2026
NVD status
Modified

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CVE-2021-20596: High severity, CVSS 7.5 | Vulnix