CVE-2026-40857 — CSRF token bypass in T-Mobile 5G Box IDU routers

CVE-2026-40857

CSRF token bypass in T-Mobile 5G Box IDU routers PUBLISHED

Description (CNA)

WNC T-Mobile 5G Box IDU router contains a cross-site request forgery (CSRF) vulnerability in the portal.cgi component. The anti-CSRF mechanism fails to validate the csrf_token_value parameter, accepting any arbitrary value as valid. This allows a remote attacker to perform unauthorized actions on the device by tricking an authenticated user into visiting a malicious website.This issue has been fixed in firmware version 1.1.0.651412

Affected (CNA)

Vendor / product	Versions
WNC / T-Mobile 5G Box IDU	affected 0 before 1.1.0.651412

CWE

CWE-352

References

https://cert.pl/posts/2026/09/CVE-2026-40854

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.