Not scored yet
CVE-2026-40854
WNC T-Mobile 5G Box IDU router contains an authentication bypass vulnerability in the portal.cgi component. The session verification mechanism improperly validates the sessionid cookie by checking for the existence of a corresponding file in /tmp/login_user. An attacker can bypass authentication by using directory entries such as "." or ".." in the cookie, allowing unauthorized access to the administration panel.This issue has been fixed in firmware version 1.1.0.651412
What this means for your business
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- Not yet scored
- CVSS v4
- 8.7
- Weakness
- CWE-290
- Assigned by
- cvd@cert.pl
Dates
- Published
- 2026-09-16
- Last modified
- 2026-09-16
- Sources
- NVD