mbNET/mbNET.rokey: Improper Validation of Specified Type of Input
CVE-2026-40851 is a high-severity improper validation of specified type of input vulnerability in mbNET/mbNET.rokey from MB connect line, with a CVSS 3.1 base score of 8.4 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, without any action from a user. Affected mbNET/mbNET.rokey versions: 8.4.4 and earlier; 8.4.4. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.13% 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 mbNET/mbNET.rokey you run against the affected versions below, and install the vendor's latest release.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| MB connect line | mbNET/mbNET.rokey | 8.4.4 and earlier; 8.4.4 | Not stated |
| MB connect line | mbNET.mini | 3.0.2 and earlier; 3.0.2 | Not stated |
| Helmholz | REX200/250 | 8.4.4 and earlier; 8.4.4 | Not stated |
| Helmholz | REX100 | 3.0.2 and earlier; 3.0.2 | 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
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (cert.vde.com).
Official description
A local attacker can perform a confusion attack on the cfgparser via a specially crafted file on an USB stick leading to code execution. This can result in a total loss of confidentiality, integrity and availability.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Validation of Specified Type of Input
The product receives input that is expected to be of a certain type, but it does not validate or incorrectly validates that the input is actually of the expected type.
More Improper Validation of Specified Type of Input vulnerabilities (CWE-1287)
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
Other references
Other vulnerabilities in mbNET/mbNET.rokey
- 7.2 High severity
- 7.8 High severity
Recent Improper Validation of Specified Type of Input vulnerabilities
- 7.3 High severity
- 7.5 High severity
- 7.7 High severity
- 8.6 High severity
- 7.4 High severity
- 7.0 High severity
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