Denial of Service (DoS) Vulnerability in MELSEC iQ-R Series Ethernet Interface Module

published 2022-11-30 3 y ago modified 2026-06-17 4 mo ago also EUVD-2022-43563

cvss: 8.6; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.0%; EPSS 1.0% chance of exploitation in 30 days, percentile 63%
public exploits: 0; none known

Improper Input Validation vulnerability in Mitsubishi Electric Corporation MELSEC iQ-R Series RJ71EN71 Firmware version "65" and prior and Mitsubishi Electric Corporation MELSEC iQ-R Series R04/08/16/32/120ENCPU Network Part Firmware version "65" and prior allows a remote unauthenticated attacker to cause a Denial of Service condition by sending specially crafted packets. A system reset is required for recovery.

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

cisa ICSA-22-335-01 updated 2022-12-01 cvss 8.6

Mitsubishi Electric MELSEC iQ-R Series

Mitsubishi Electric MELSEC iQ-R R04/08/16/32/120ENCPU <= 65 Mitsubishi Electric MELSEC iQ-R RJ71EN71 <= 65
affected: mitigation “Mitsubishi Electric has fixed the vulnerability: RJ71EN71: Update firmware version to “66” or later. R04/08/16/32/120ENCPU: Update network part firmware version to “66” or later.” mitsubishielectric.com

From CISA ICS and IT advisories (CSAF, https://github.com/cisagov/CSAF), a U.S. Government work; changed: reduced to products, statuses and remediations. CISA notification · csaf

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 18 mo ago (2025-04-24)

Exploit prediction

1.02% chance of exploitation in the next 30 days, higher than 63% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.6	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

Mitsubishi Electric Corporation MELSEC iQ-R Series RJ71EN71
Mitsubishi Electric Corporation MELSEC iQ-R Series R04/08/16/32/120ENCPU

Classification

Weakness

CWE-20 Improper Input Validation

References

mitsubishielectric.com /en/psirt/vulnerability/pdf/2022-017_en.pdf
vendor-advisory
jvn.jp /vu/JVNVU94702422
third-party-advisory

Sources

CVE List CVE-2022-40265
NVD CVE-2022-40265

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Summary