MB Connect Line mbNET/mbNET.rokey/mbNET.mini up to 8.4.4 File improper validation of specified type of input

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.9$0-$5k0.00

Summaryinfo

A vulnerability was found in MB Connect Line mbNET, mbNET.rokey and mbNET.mini up to 8.4.4. It has been classified as critical. This issue affects some unknown processing of the component File Handler. This manipulation causes improper validation of specified type of input. This vulnerability is tracked as CVE-2026-40851. The attack is restricted to local execution. No exploit exists.

Detailsinfo

A vulnerability has been found in MB Connect Line mbNET, mbNET.rokey and mbNET.mini up to 8.4.4 and classified as critical. Affected by this vulnerability is an unknown code block of the component File Handler. The manipulation with an unknown input leads to a improper validation of specified type of input vulnerability. The CWE definition for the vulnerability is CWE-1287. 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. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

The weakness was disclosed by Moritz Abrell as VDE-2026-054. It is possible to read the advisory at certvde.com. This vulnerability is known as CVE-2026-40851 since 04/15/2026. The exploitation appears to be easy. Attacking locally is a requirement. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 05/27/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.1
VulDB Meta Temp Score: 7.9

VulDB Base Score: 7.8
VulDB Temp Score: 7.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.4
CNA Vector (CERTVDE): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper validation of specified type of input
CWE: CWE-1287 / CWE-20
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

04/15/2026 CVE reserved
05/27/2026 +42 days Advisory disclosed
05/27/2026 +0 days VulDB entry created
05/27/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: VDE-2026-054
Researcher: Moritz Abrell
Status: Not defined

CVE: CVE-2026-40851 (🔒)
GCVE (CVE): GCVE-0-2026-40851
GCVE (VulDB): GCVE-100-366007

Entryinfo

Created: 05/27/2026 11:56
Changes: 05/27/2026 11:56 (63)
Complete: 🔍
Cache ID: 216::103

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