CVE-2026-40855: CWE-78 Improper neutralization of special elements used in an OS command ('OS command injection') in WNC T-Mobile 5G Box IDU
WNC T-Mobile 5G Box IDU router is vulnerable to a command injection. The vulnerability exists in the ping functionality within the /cgi-bin/portal.cgi endpoint, specifically affecting the ping_ip, ping_size, and ping_times POST parameters. The root cause is the failure to verify and sanitize user-supplied input before incorporating it into a system command. This allows an authenticated attacker to execute arbitrary commands on the shell and gain root access to the system.This issue has been fixed in firmware version 1.1.0.651412
AI Analysis
Technical Summary
CVE-2026-40855 is an OS command injection vulnerability (CWE-78) in the WNC T-Mobile 5G Box IDU router. The issue exists in the ping functionality of the /cgi-bin/portal.cgi endpoint, specifically in the handling of the ping_ip, ping_size, and ping_times POST parameters. Due to failure to properly validate and sanitize user input before incorporating it into system commands, an authenticated attacker can execute arbitrary commands on the device's shell, gaining root access. The vulnerability affects all firmware versions prior to 1.1.0.651412, where it has been fixed.
Potential Impact
An authenticated attacker can exploit this vulnerability to execute arbitrary commands on the router's operating system shell with root privileges. This can lead to full system compromise, including unauthorized control over the device and potential disruption of network services.
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. No other mitigation is required as the issue is resolved by this official firmware update.
CVE-2026-40855: CWE-78 Improper neutralization of special elements used in an OS command ('OS command injection') in WNC T-Mobile 5G Box IDU
Description
WNC T-Mobile 5G Box IDU router is vulnerable to a command injection. The vulnerability exists in the ping functionality within the /cgi-bin/portal.cgi endpoint, specifically affecting the ping_ip, ping_size, and ping_times POST parameters. The root cause is the failure to verify and sanitize user-supplied input before incorporating it into a system command. This allows an authenticated attacker to execute arbitrary commands on the shell and gain root access to the system.This issue has been fixed in firmware version 1.1.0.651412
CVSS v4.0
Score 9.3critical
Affected software
WNC
T-Mobile 5G Box IDU
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-40855 is an OS command injection vulnerability (CWE-78) in the WNC T-Mobile 5G Box IDU router. The issue exists in the ping functionality of the /cgi-bin/portal.cgi endpoint, specifically in the handling of the ping_ip, ping_size, and ping_times POST parameters. Due to failure to properly validate and sanitize user input before incorporating it into system commands, an authenticated attacker can execute arbitrary commands on the device's shell, gaining root access. The vulnerability affects all firmware versions prior to 1.1.0.651412, where it has been fixed.
Potential Impact
An authenticated attacker can exploit this vulnerability to execute arbitrary commands on the router's operating system shell with root privileges. This can lead to full system compromise, including unauthorized control over the device and potential disruption of network services.
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. No other mitigation is required as the issue is resolved by this official firmware update.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- CERT-PL
- Date Reserved
- 2026-04-15T11:10:34.849Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6aaa7e3555bf5e2cf5884acc
Added to database: 09/16/2026, 11:32:05 UTC
Last enriched: 09/16/2026, 11:47:19 UTC
Last updated: 09/17/2026, 00:28:42 UTC
Views: 15
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