What’s Vulnerable › Vulnerabilities
CVE-2026-40855: Command Injection in T-Mobile 5G Box IDU router via ping functionality
- Severity: critical (CVSS 9.3 v4.0)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 1.6% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-09-16 · updated 2026-09-28
- Weakness: CWE-78
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
Affected products
- WNC T-Mobile 5G Box IDU: before 1.1.0.651412 — fixed in 1.1.0.651412
How to fix
Upgrade to a fixed version: WNC T-Mobile 5G Box IDU 1.1.0.651412. Check the vendor advisory for mitigations.
References
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