CVE-2026-40856: CWE-306 Missing authentication for critical function in WNC T-Mobile 5G Box IDU
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
AI Analysis
Technical Summary
CVE-2026-40856 is an improper access control vulnerability (CWE-306) in the WNC T-Mobile 5G Box IDU router. The vulnerability exists because the wnc_maccheck.cgi endpoint is accessible without authentication, enabling remote attackers to retrieve sensitive configuration data such as the administrator web password, WiFi passphrase, and technical device information. This flaw has been addressed in firmware version 1.1.0.651412.
Potential Impact
An unauthenticated remote attacker can retrieve sensitive configuration information from the device, including administrator credentials and WiFi passphrases, potentially leading to unauthorized access and control over the device and network.
Mitigation Recommendations
Upgrade the WNC T-Mobile 5G Box IDU router firmware to version 1.1.0.651412 or later, where this vulnerability has been fixed.
CVE-2026-40856: CWE-306 Missing authentication for critical function in WNC T-Mobile 5G Box IDU
Description
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
CVSS v4.0
Score 7.1high
Affected software
WNC
T-Mobile 5G Box IDU
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-40856 is an improper access control vulnerability (CWE-306) in the WNC T-Mobile 5G Box IDU router. The vulnerability exists because the wnc_maccheck.cgi endpoint is accessible without authentication, enabling remote attackers to retrieve sensitive configuration data such as the administrator web password, WiFi passphrase, and technical device information. This flaw has been addressed in firmware version 1.1.0.651412.
Potential Impact
An unauthenticated remote attacker can retrieve sensitive configuration information from the device, including administrator credentials and WiFi passphrases, potentially leading to unauthorized access and control over the device and network.
Mitigation Recommendations
Upgrade the WNC T-Mobile 5G Box IDU router firmware to version 1.1.0.651412 or later, where this vulnerability has been fixed.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- CERT-PL
- Date Reserved
- 2026-04-15T11:10:34.850Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6aaa7e3555bf5e2cf5884acd
Added to database: 09/16/2026, 11:32:05 UTC
Last enriched: 09/16/2026, 11:47:16 UTC
Last updated: 09/17/2026, 00:40:07 UTC
Views: 9
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