VDB-405707 · CVE-2026-40856 · GCVE-0-2026-40856

WNC T-Mobile 5G Box IDU prior 1.1.0.651412 Mac Check wnc_maccheck.cgi access control

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
5.1	$0-$5k	0.00

Summaryinfo

A vulnerability, which was classified as problematic, has been found in WNC T-Mobile 5G Box IDU. Impacted is an unknown function of the file wnc_maccheck.cgi of the component Mac Check. The manipulation leads to access control. This vulnerability is uniquely identified as CVE-2026-40856. The attack is possible to be carried out remotely. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in WNC T-Mobile 5G Box IDU and classified as problematic. This issue affects an unknown functionality of the file wnc_maccheck.cgi of the component Mac Check. The manipulation with an unknown input leads to a access control vulnerability. Using CWE to declare the problem leads to CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. Impacted is confidentiality. The summary by CVE is:

WNC T-Mobile 5G Box IDU router is vulnerable to improper access control. The vulnerability exists in the wnc_maccheck.cgi endpoint, which is accessible without authentication. It allows a remote attacker to retrieve sensitive configuration data, including the administrator web password, WiFi passphrase, and technical device information.This issue has been fixed in firmware version 1.1.0.651412

It is possible to read the advisory at cert.pl. The identification of this vulnerability is CVE-2026-40856 since 04/15/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1068 according to MITRE ATT&CK.

Upgrading to version 1.1.0.651412 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

Name

T-Mobile 5G Box IDU

CPE 2.3info

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CPE 2.2info

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CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

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

Exploitinginfo

Class: Access control
CWE: CWE-284 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: T-Mobile 5G Box IDU 1.1.0.651412

Timelineinfo

04/15/2026 CVE reserved
09/16/2026 +154 days Advisory disclosed
09/16/2026 +0 days VulDB entry created
09/16/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: cert.pl
Status: Confirmed

CVE: CVE-2026-40856 (🔒)
GCVE (CVE): GCVE-0-2026-40856
GCVE (VulDB): GCVE-100-405707

Entryinfo

Created: 09/16/2026 14:02
Changes: 09/16/2026 14:02 (66)
Complete: 🔍
Cache ID: 216::103