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Gt Softgot2000Application · Mitsubishielectric

CVE-2021-20592

HIGH · 7.5 CVSS v3.1 Published 2021-08-05
Fix available
A fix is available. Upgrade to after 1.256s or later.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Missing synchronization vulnerability in GOT2000 series GT27 model communication driver versions 01.19.000 through 01.39.010, GT25 model communication driver versions 01.19.000 through 01.39.010 and GT23 model communication driver versions 01.19.000 through 01.39.010 and GT SoftGOT2000 versions 1.170C through 1.256S allows a remote unauthenticated attacker to cause DoS condition on the MODBUS/TCP slave communication function of the products by rapidly and repeatedly connecting and disconnecting to and from the MODBUS/TCP communication port on a target. Restart or reset is required to recover.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Missing synchronization (race condition) in the MODBUS/TCP slave communication driver allows remote unauthenticated attackers to cause denial of service by rapidly connecting and disconnecting to the MODBUS/TCP port, exhausting resources or causing a deadlock in the driver.

MitigationUpdate GOT2000 firmware to version 01.40.000 or later (or SoftGOT2000 to 1.257T or later); implement network segmentation and firewall rules to restrict access to MODBUS/TCP port 502 to authorized hosts only.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Gt Softgot2000Application
Affected:>= 1.170c, <= 1.256s
Got2000 Gt27 FirmwareOperating system
Affected:>= 01.19.000, <= 01.39.010
Got2000 Gt25 FirmwareOperating system
Affected:>= 01.19.000, <= 01.39.010
Got2000 Gt23 FirmwareOperating system
Affected:>= 01.19.000, <= 01.39.010

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify the Mitsubishi Electric product in use
    Determine if the system uses SoftGOT2000 software on a PC or a GOT2000 HMI device (GT27, GT25, or GT23 series)
    Affected if The product is SoftGOT2000 or any GOT2000 HMI model (GT27/GT25/GT23)
  2. Check if MODBUS/TCP communication is enabled
    Inspect the project settings or device configuration for MODBUS/TCP slave driver configuration. For SoftGOT2000, check the GT Designer3 project settings. For GOT2000 devices, check the device HMI settings via GT Designer3 or the device web interface
    Affected if MODBUS/TCP is configured and active on the device
  3. Verify SoftGOT2000 software version
    Open Windows Programs and Features (or equivalent), locate Mitsubishi Electric GT SoftGOT2000, and note the installed version number
    Affected if The version is >= 1.170c and <= 1.256s (vulnerable range)
  4. Verify GOT2000 HMI firmware version
    Access the GOT2000 device via GT Designer3 or the device web interface and check the firmware version displayed in system information or device diagnostics
    Affected if The firmware version is >= 01.19.000 and <= 01.39.010 (vulnerable range)
  5. Confirm MODBUS/TCP port 502 exposure
    Use a network scanner or check firewall rules to determine if port 502 (MODBUS/TCP) is accessible from network segments outside the control system
    Affected if Port 502 is exposed to untrusted network segments

The environment is affected if MODBUS/TCP is enabled on a SoftGOT2000 version 1.170c-1.256s or a GOT2000 HMI (GT27/GT25/GT23) firmware version 01.19.000-01.39.010, and port 502 is network-accessible.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Upgrade available Upgrade to a release after 1.256s
Interim mitigation

Update GOT2000 firmware to version 01.40.000 or later (or SoftGOT2000 to 1.257T or later); implement network segmentation and firewall rules to restrict access to MODBUS/TCP port 502 to authorized hosts only.

Fix this in Gt Softgot2000 Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing8.0 h
  • Review / QA4.0 h
24.0 hours of engineering $4,160
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-20592 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data