CVE-2021-20596

Severity Score

7.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

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.

Una desreferencia de puntero NULL en MELSEC-F Series FX3U-ENET versiones de firmware 1.14 y anteriores, FX3U-ENET-L versiones de firmware 1.14 y anteriores, y FX3U-ENET-P502 versiones de firmware 1.14 y anteriores, permite a un atacante remoto no autenticado causar una condición de Denegación de Servicio en la comunicación mediante el envío de paquetes especialmente diseñados. El control por parte del PLC de la serie MELSEC-F no está afectado y es requerido un reinicio del sistema para la recuperación

*Credits: N/A

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Network

Attack Complexity

Low

Authentication

None

Confidentiality

None

Integrity

None

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2020-12-17 CVE Reserved
2021-07-22 CVE Published
2024-07-10 EPSS Updated
2024-08-03 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-476: NULL Pointer Dereference

CAPEC

References (3)

URL	Tag	Source
https://us-cert.cisa.gov/ics/advisories/icsa-21-201-01	Third Party Advisory

URL	Date	SRC

URL	Date	SRC
https://jvn.jp/vu/JVNVU94348759/index.html	2021-08-02
https://www.mitsubishielectric.com/en/psirt/vulnerability/pdf/2021-006_en.pdf	2021-08-02

URL	Date	SRC

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Mitsubishielectric Search vendor "Mitsubishielectric"		Fx3u-enet-l Firmware Search vendor "Mitsubishielectric" for product "Fx3u-enet-l Firmware"				<= 1.14 Search vendor "Mitsubishielectric" for product "Fx3u-enet-l Firmware" and version " <= 1.14"		-		Affected
Mitsubishielectric Search vendor "Mitsubishielectric"		Fx3u-enet-p502 Firmware Search vendor "Mitsubishielectric" for product "Fx3u-enet-p502 Firmware"				<= 1.14 Search vendor "Mitsubishielectric" for product "Fx3u-enet-p502 Firmware" and version " <= 1.14"		-		Affected
Mitsubishielectric Search vendor "Mitsubishielectric"		Fx3u-enet Firmware Search vendor "Mitsubishielectric" for product "Fx3u-enet Firmware"				<= 1.14 Search vendor "Mitsubishielectric" for product "Fx3u-enet Firmware" and version " <= 1.14"		-		Affected