CVE-2021-20601Network attack vector

System malfunction via unchecked network device-value writes

Published Nov 23, 2021 · Updated Aug 3, 2024

Improper input validation in all Mitsubishi Electric GOT and GT SoftGOT2000 versions allows remote attackers to overwrite device values. Network-originated writes bypass GUI input-range enforcement, so the device accepts a value outside the configured limit. No authentication or user interaction is required, and an out-of-range device value can cause the controlled system to malfunction.

CVSS severity7.5
High
EPSS probability2.43%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in all Mitsubishi Electric GOT and GT SoftGOT2000 versions allows remote attackers to overwrite device values. Network-originated writes bypass GUI input-range enforcement, so the device accepts a value outside the configured limit. No authentication or user interaction is required, and an out-of-range device value can cause the controlled system to malfunction.

The record

CVE
CVE-2021-20601
Published
Nov 23, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-20, T0831
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 23, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5JPCERT/CCCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
7.8NIST NVDAV:N/AC:L/Au:N/C:N/I:C/A:N
7.5Mitsubishi Electric CorporationCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T0831Manipulation of Control

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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