Security readout for executives and security teams
Plain-English summary
This issue can make affected Mitsubishi GOT2000 and GT SoftGOT2000 systems stop handling MODBUS/TCP slave communication. An unauthenticated remote actor who can reach the MODBUS/TCP port could trigger a denial of service, and recovery requires a restart or reset. The main business risk is operational disruption, not data theft.
Executive priority
Handle as a moderate OT availability risk. It deserves priority where the affected MODBUS/TCP function supports production operations or can be reached from weakly controlled networks. There is no supplied evidence of active exploitation or data compromise.
Technical view
CVE-2021-20592 is a missing synchronization flaw in specified GOT2000 GT27, GT25, GT23 communication drivers and GT SoftGOT2000 versions. The described impact is denial of service in the MODBUS/TCP slave communication function after repeated connection churn to the MODBUS/TCP communication port. No CVSS, CWE, CPE, or patch detail is included in the supplied bundle.
Likely exposure
Exposure is most likely where affected Mitsubishi GOT2000 or GT SoftGOT2000 versions are deployed and the MODBUS/TCP slave communication port is reachable by untrusted or broad internal networks. Internet exposure is not stated in the sources and should not be assumed without asset evidence.
Exploitation context
The source bundle describes a remote unauthenticated denial-of-service condition. It does not cite active exploitation, public exploit availability, or CISA KEV listing. Treat exploitation status as unconfirmed, while recognizing that network reachability to the MODBUS/TCP port is the key enabling condition.
Researcher notes
Evidence is limited to the CVE description and referenced advisories. The bundle identifies affected versions and DoS behavior but provides no CVSS vector, CWE, CPE, exploit status, or explicit fix text. Validate vendor advisory details before asserting patch versions.
Mitigation direction
- Check Mitsubishi Electric and JVN guidance for supported updates or official mitigations.
- Restrict MODBUS/TCP access to authorized OT hosts and management networks only.
- Remove affected systems from untrusted or broadly routed network segments.
- Plan restart or reset procedures for affected devices if service is disrupted.
- Prioritize remediation where MODBUS/TCP supports production-critical monitoring or control workflows.
Validation and detection
- Inventory GOT2000 GT27, GT25, GT23, and GT SoftGOT2000 deployments and versions.
- Confirm whether MODBUS/TCP slave communication is enabled on each affected asset.
- Verify network paths to the MODBUS/TCP communication port from user and external segments.
- Review monitoring for unexpected connection churn or communication outages.
- Avoid stress testing production systems; use a lab environment if validation is required.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CVE-2021-20592 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://www.mitsubishielectric.com/en/psirt/vulnerability/pdf/2021-007_en.pdfCVE reference · x_refsource_MISC
- https://jvn.jp/vu/JVNVU92414172/index.htmlCVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.