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CVE-2021-20591

Published: Jun 11, 2021Updated: Nov 21, 2024 Sources: CVE List NVD csafCWE-400
7.5HIGH
NVD MITRE
EPSS Score
1.5%
Top 28.2%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
Not available

Description

Uncontrolled Resource Consumption vulnerability in Mitsubishi Electric MELSEC iQ-R series CPU modules (R00/01/02CPU all versions, R04/08/16/32/120(EN)CPU all versions, R08/16/32/120SFCPU all versions, R08/16/32/120PCPU all versions, R08/16/32/120PSFCPU all versions) allows a remote unauthenticated attacker to prevent legitimate clients from connecting to the MELSOFT transmission port (TCP/IP) by not closing a connection properly, which may lead to a denial of service (DoS) condition.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
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Weaknesses

CWE-400

Affected Products

mitsubishielectric
commercial·JPaka mitsubishi electric
r00cpu firmware
ICS / OT / IoT
r01cpu firmware
ICS / OT / IoT
r02cpu firmware
ICS / OT / IoT
r04cpu firmware
ICS / OT / IoT
r08cpu firmware
ICS / OT / IoT
r16cpu firmware
ICS / OT / IoT
r32cpu firmware
ICS / OT / IoT
r120cpu firmware
ICS / OT / IoT
and 13 more affected products View all →

Exploitability

Official Patch Available
Is your org exposed to CVE-2021-20591?We can run the check for you — a free external exposure review, no install. Check my exposure

Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Impact
View detailed technique mapping

References

https://jvn.jp/vu/JVNVU98060539/index.html
jvn.jp
https://www.mitsubishielectric.com/en/psirt/vulnerability/pdf/2021-003_en.pdf
mitsubishielectric.com
https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/OT/white/2021/icsa-21-147-05.json
raw.githubusercontent.com
and 5 more references View all →

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