vulnerability

CVE-2026-40854

· published 2026-09-16 · 1 on the wire

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

Exploited in the wild

Not on KEV

Not in CISA's Known Exploited Vulnerabilities catalogue as of the last daily pull. Absence is not proof of safety.

EPSS · 30-day forecast

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FIRST has not scored this id yet.

CVSS · NVD

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no vector published

Internet exposure

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No exposure census on this CVE's dispatches.

On the wire1

16 SepVulnerabilities in WNC T-Mobile 5G Box IDU routersVULN

References

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