OpenBlocks IoT DX1 (FW5.0.x): Authentication Bypass Using an Alternate Path or Channel
CVE-2026-21411 is a high-severity authentication bypass using an alternate path or channel vulnerability in OpenBlocks IoT DX1 (FW5.0.x) from Plat'Home, with a CVSS 4.0 base score of 8.7 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. Affected OpenBlocks IoT DX1 (FW5.0.x) versions: all versions prior to FW5.0.8. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.37% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of OpenBlocks IoT DX1 (FW5.0.x) you run against the affected versions below, and install the vendor's latest release.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Plat'Home | OpenBlocks IoT DX1 (FW5.0.x) | all versions prior to FW5.0.8 | Not stated |
| Plat'Home | OpenBlocks IoT EX/BX models (FW5.0.x) | all versions prior to FW5.0.8 | Not stated |
| Plat'Home | OpenBlocks IX9 models with FW (FW5.0.x) | all versions prior to FW5.0.8 | Not stated |
| Plat'Home | OpenBlocks IoT VX2 (FW5.0.x) | all versions prior to FW5.0.8 | Not stated |
| Plat'Home | OpenBlocks IDM RX1 (FW5.0.x) | all versions prior to FW5.0.8 | Not stated |
| Plat'Home | OpenBlocks IoT FX1 (FW5.0.x) | all versions prior to FW5.0.8 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- AdjacentThe attacker must be on the same local network segment.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Attack requirements
- NoneThe attack does not depend on a particular deployment or configuration.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Confidentiality (vulnerable system)
- HighSerious loss of confidentiality on the vulnerable system.
- Integrity (vulnerable system)
- HighSerious loss of integrity on the vulnerable system.
- Availability (vulnerable system)
- HighSerious loss of availability on the vulnerable system.
- Confidentiality (other systems)
- NoneNo loss of confidentiality on systems beyond the vulnerable one.
- Integrity (other systems)
- NoneNo loss of integrity on systems beyond the vulnerable one.
- Availability (other systems)
- NoneNo loss of availability on systems beyond the vulnerable one.
Vector: 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. Scored by CNA (jpcert.or.jp).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.7 | High | CNA (jpcert.or.jp) |
| CVSS 3.0 | 8.8 | High | CNA (jpcert.or.jp) |
Official description
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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Authentication Bypass Using an Alternate Path or Channel
The product requires authentication, but the product has an alternate path or channel that does not require authentication.
How developers prevent this class of flaw
- Funnel all access through a single choke point to simplify how users can access a resource. For every access, perform a check to determine if the user has permissions to access the resource.
More Authentication Bypass Using an Alternate Path or Channel vulnerabilities (CWE-288)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Recent Authentication Bypass Using an Alternate Path or Channel vulnerabilities
- 9.8 Critical severity
- 9.1 Critical severity
- 9.8 Critical severity
- 9.8 Critical severity
- 7.2 High severity
- 9.8 Critical severity
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