CVE-2026-40855
Critical
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
SeverityCritical
CVSS9.3
Exploit probability—
ProductT-Mobile 5G Box IDU
PublishedSep 16, 2026
First seenSep 16, 2026
Weakness typeCWE-78OS command injection
How to fix
Update
- WNC T-Mobile 5G Box IDU1.1.0.651412 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| WNC T-Mobile 5G Box IDU | v < 1.1.0.651412 | 1.1.0.651412 |
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