High severity · published Jun 11, 2021
CVE-2021-20591
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,…
7.5
CVSS
1.5%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.5% · higher than 74% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RF
R00cpu Firmware · Mitsubishielectric
All versions, or not specified · source: NVD
RF
R01cpu Firmware · Mitsubishielectric
All versions, or not specified · source: NVD
RF
R02cpu Firmware · Mitsubishielectric
All versions, or not specified · source: NVD
RF
R04cpu Firmware · Mitsubishielectric
All versions, or not specified · source: NVD
RF
R08cpu Firmware · Mitsubishielectric
All versions, or not specified · source: NVD
RF
R08pcpu Firmware · Mitsubishielectric
All versions, or not specified · source: NVD
RF
R08psfcpu Firmware · Mitsubishielectric
All versions, or not specified · source: NVD
RF
R08sfcpu Firmware · Mitsubishielectric
All versions, or not specified · source: NVD
RF
R120cpu Firmware · Mitsubishielectric
All versions, or not specified · source: NVD
RF
R120pcpu Firmware · Mitsubishielectric
All versions, or not specified · source: NVD
RF
R120psfcpu Firmware · Mitsubishielectric
All versions, or not specified · source: NVD
RF
R120sfcpu Firmware · Mitsubishielectric
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-20591
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-20591
Third Party Advisory
https://jvn.jp/vu/JVNVU98060539/index.html
Vendor Advisory
https://www.mitsubishielectric.com/en/psirt/vulnerability/pdf/2021-003_en.pdf
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