CVE-2026-40855

CVE-2026-40855

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

Vulnerability class: Command Injection (OS Command Injection)

Published · last modified .

EPSS exploit prediction

EPSS: 0.016 (75.7th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 76th percentile — 75.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-40855: held from 0.016 to 0.016.

EPSS over last 30 days · oldest: 0.016 · newest: 0.016 · change: 0.000

Weakness classification (CWE)

References