Vulnerability-Lookup

JVNDB-2026-001001

Vulnerability from jvndb - Published: 2026-01-07 01:46 - Updated:2026-01-07 01:46

Severity

8.8 (High) - cvssV3_0 - CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Summary

Authentication bypass vulnerability in OpenBlocks series

Details

OpenBlocks series provided by Plat'Home Co.,Ltd. contains the following vulnerability.

Authentication bypass (CWE-288) - CVE-2026-21411

Chuya Hayakawa of 00One, Inc. reported this vulnerability to JPCERT/CC. JPCERT/CC coordinated with the developer.

References

Type

URL

	JVN	https://jvn.jp/en/vu/JVNVU97172240/index.html
	CVE	https://www.cve.org/CVERecord?id=CVE-2026-21411
	Authentication Bypass Using an Alternate Path or Channel(CWE-288)	https://cwe.mitre.org/data/definitions/288.html

Impacted products

Vendor

Product

	Plat'Home Co., Ltd.	OpenBlocks IDM RX1
	Plat'Home Co., Ltd.	OpenBlocks IoT DX1
	Plat'Home Co., Ltd.	OpenBlocks IoT EX/BX models
	Plat'Home Co., Ltd.	OpenBlocks IoT FX1
	Plat'Home Co., Ltd.	OpenBlocks IoT VX2
	Plat'Home Co., Ltd.	OpenBlocks IX9 models with FW

Show details on JVN DB website

JSON

To clipboard

{
  "@rdf:about": "https://jvndb.jvn.jp/en/contents/2026/JVNDB-2026-001001.html",
  "dc:date": "2026-01-07T10:46+09:00",
  "dcterms:issued": "2026-01-07T10:46+09:00",
  "dcterms:modified": "2026-01-07T10:46+09:00",
  "description": "OpenBlocks series provided by Plat\u0027Home Co.,Ltd. contains the following vulnerability.\u003cul\u003e\u003cli\u003eAuthentication bypass (CWE-288) - CVE-2026-21411\u003c/li\u003e\u003c/ul\u003eChuya Hayakawa of 00One, Inc. reported this vulnerability to JPCERT/CC.\r\nJPCERT/CC coordinated with the developer.",
  "link": "https://jvndb.jvn.jp/en/contents/2026/JVNDB-2026-001001.html",
  "sec:cpe": [
    {
      "#text": "cpe:/o:plathome:openblocks_idm_rx1_firmware",
      "@product": "OpenBlocks IDM RX1",
      "@vendor": "Plat\u0027Home Co., Ltd.",
      "@version": "2.2"
    },
    {
      "#text": "cpe:/o:plathome:openblocks_iot_dx1_firmware",
      "@product": "OpenBlocks IoT DX1",
      "@vendor": "Plat\u0027Home Co., Ltd.",
      "@version": "2.2"
    },
    {
      "#text": "cpe:/o:plathome:openblocks_iot_ex_bx_firmware",
      "@product": "OpenBlocks IoT EX/BX models",
      "@vendor": "Plat\u0027Home Co., Ltd.",
      "@version": "2.2"
    },
    {
      "#text": "cpe:/o:plathome:openblocks_iot_fx1_firmware",
      "@product": "OpenBlocks IoT FX1",
      "@vendor": "Plat\u0027Home Co., Ltd.",
      "@version": "2.2"
    },
    {
      "#text": "cpe:/o:plathome:openblocks_iot_vx2_firmware",
      "@product": "OpenBlocks IoT VX2",
      "@vendor": "Plat\u0027Home Co., Ltd.",
      "@version": "2.2"
    },
    {
      "#text": "cpe:/o:plathome:openblocks_ix9_with_fw_firmware",
      "@product": "OpenBlocks IX9 models with FW",
      "@vendor": "Plat\u0027Home Co., Ltd.",
      "@version": "2.2"
    }
  ],
  "sec:cvss": {
    "@score": "8.8",
    "@severity": "High",
    "@type": "Base",
    "@vector": "CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
    "@version": "3.0"
  },
  "sec:identifier": "JVNDB-2026-001001",
  "sec:references": [
    {
      "#text": "https://jvn.jp/en/vu/JVNVU97172240/index.html",
      "@id": "JVNVU#97172240",
      "@source": "JVN"
    },
    {
      "#text": "https://www.cve.org/CVERecord?id=CVE-2026-21411",
      "@id": "CVE-2026-21411",
      "@source": "CVE"
    },
    {
      "#text": "https://cwe.mitre.org/data/definitions/288.html",
      "@id": "CWE-288",
      "@title": "Authentication Bypass Using an Alternate Path or Channel(CWE-288)"
    }
  ],
  "title": "Authentication bypass vulnerability in OpenBlocks series"
}

CVE-2026-21411 (GCVE-0-2026-21411)

Vulnerability from cvelistv5 – Published: 2026-01-06 06:34 – Updated: 2026-01-06 14:49

Summary

Authentication bypass issue exists in OpenBlocks series versions prior to FW5.0.8, which may allow an attacker to bypass administrator authentication and change the password.

Severity

8.8 (High)


                        
                          CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

8.7 (High)


                        
                          CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-01-06 14:47 UTC

CWE

CWE-288 - Authentication Bypass Using an Alternate Path or Channel

Assigner

jpcert jpcert root

References

2 references

URL	Tags
https://www.plathome.co.jp/support/software/fw5/d…
https://jvn.jp/en/vu/JVNVU97172240/

Impacted products

6 products

Vendor	Product	Version
Plat'Home Co.,Ltd.	OpenBlocks IoT DX1 (FW5.0.x)	Affected: all versions prior to FW5.0.8
Plat'Home Co.,Ltd.	OpenBlocks IoT EX/BX models (FW5.0.x)	Affected: all versions prior to FW5.0.8
Plat'Home Co.,Ltd.	OpenBlocks IX9 models with FW (FW5.0.x)	Affected: all versions prior to FW5.0.8
Plat'Home Co.,Ltd.	OpenBlocks IoT VX2 (FW5.0.x)	Affected: all versions prior to FW5.0.8
Plat'Home Co.,Ltd.	OpenBlocks IDM RX1 (FW5.0.x)	Affected: all versions prior to FW5.0.8
Plat'Home Co.,Ltd.	OpenBlocks IoT FX1 (FW5.0.x)	Affected: all versions prior to FW5.0.8

Show details on NVD website

JSON

To clipboard

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                "id": "CVE-2026-21411",
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.